As President Bashar al-Assad discussed a ceasefire for Syria last week, his tanks continued to crush northern rebel strongholds. In this dispatch from the town of Saraqeb, John Cantlie describes an assault at first hand.

The sound of the caterpillar tracks could be felt as much as heard, a deep rumble that sent a rattle through windows and a tremble of fear through the guts.

Then we saw them. Huge Soviet-made T72s, accompanied by troop carriers driving slowly into town, extra plates welded onto the sides to deflect rocket-propelled grenades. It was just after 9.30am, and the tanks were coming to Saraqeb.

"Light the tyres!"

The rebels of the Free Syrian Army in Saraqeb, a farming town of 30,000 in northern Syria, are better organised than many in the surrounding Idlib province. Squaring themselves away into formation around the central marketplace, they poured petrol on to truck tyres and lit them sending plumes of thick black smoke into the air, obscuring the sun and - hopefully - the tank gunners´ visibility.

Still the tanks came, driving into town one after another. The troop carriers stopped to take up holding positions, while the T72s turned in pairs to face towards the centre.

I had been smuggled into Saraqeb last weekend by a local guerrilla unit, keen to show the world that despite playing along with international efforts to broker a ceasefire, President Bashar al- Assad was continuing to use all-out force to crush his opponents.

While he agreed last week to a six-point peace plan brokered by the veteran diplomat, Kofi Annan, what I saw for myself suggests the Syrian leader intends anything but.

As Syrian army snipers deployed to Saraqeb´s high buildings to provide covering fire, the rebel fighters around me took up positions on street corners and pavements.

Their pick-up trucks screeched to a halt, bringing reinforcements, rocket-propelled grenades and improvised bombs built from gas bottles and steel pipes which are placed against kerbs and disguised with cardboard. Then came the click-clack of 200 Kalashnikovs being loaded, a few unaimed rounds loosed off in anger. For five tense minutes, nothing happened.

Then the T72s began to advance toward the market square, the shriek of their tracks reverberating up the street as white smoke belched from their engines. Together with several dozen rebels, I watched from 100 yards away as the gun turrets swept first left, then right, scanning the side alleys for threats. For now, their 125mm cannon remained silent.

"Allahu Akbar!"

Chanting the rebel cry of "God is great", one fighter shouldered his RPG launcher, aimed down the tube and fired. The rocket flew straight and true, catching the lead T72 just to the left of the driver´s porthole. A cheer went up, the rebels punching the air in celebration. Yet no-one had noticed the rocket had not exploded, but merely shattered into a hundred useless pieces of metal. And that was when the tanks opened fire.

The first shells punched into nearby buildings, producing a shockwave of sound and a sea of grey dirt and dust that rolled up the road like a tsunami. Fist-size pieces of hot shrapnel sliced through the air, decapitating one fighter instantly.

His rifle clattered against a wall as his friends dragged his headless torso from the line of fire. The body was bloodless, cauterized. Another rebel caught a piece of shell in his leg, a deep femoral bleed that left a crimson trail across the road.

"RPGs! Get more RPGs up here!" shouted one game fighter, to little avail. With no real chain of command, the rebels use as much energy arguing amongst themselves as they do fighting the enemy. As panicky bickering ensued, a woman ushered her terrified children out of the door. "Please don´t shoot from here," she begged the rebels. "My mother is very old and cannot move - if you shoot at them here they will destroy our house." "We will use our bombs to stop them, I promise," replied a fighter. But home-made bombs do little against a battle tank. As the T72s began shooting at the base of buildings to make them collapse Muktar Nassar, a young man in white robes, ran up with another RPG, one of the few with a functioning warhead. Clearly terrified at being just 50 yards from a T72, he briefly got the perfect firing angle to hit the tank´s more vulnerable side armour, only to be forced to run for cover again as the tank behind his target fired again.

"No good, it´s no good" Muktar muttered as we retreated, showered again in dust. Up above, sniper rounds peppered the mosque minarets. The fighting was brutally one-sided. As a show of force it was absolute.

By 3pm the rebels knew it was over, retreating to cover to smoke cigarettes, leaving the tanks to roam and shell as they pleased. In the space of just a few hours, Saraqeb had been broken. Then it was everyone for themselves. Some families remained in their homes, hoping for the best, others threw belongings into cars and headed out of town.

The guerrillas, meanwhile, staged their own chaotic withdrawal, driving cars at 100mph down small country roads to villages beyond range of the shells, while an army helicopter circled overhead. If the tanks hadn´t killed the rebels, their driving may have finished the job.

"What could we do against that?" lamented Abdul Karali, a student whose family live in Saraqeb. "We´re not soldiers, we have no training and few weapons."

Seven were killed in the fighting that day and 28 wounded. Next morning, Sunday, an attempted rebel counter-attack ended in retreat, the fighters stranding themselves between two tank positions, 500 metres of open ground and a footbridge in full view of government machine guns.

The uprising in Syria is turning into a hit-and-run guerilla war, with the rebels disrupting government forces any way they can. But without money, training or anti-tank weapons, they have little bite. Until the big city businessmen from Damascus and Aleppo commit to the fight, Syria´s revolution is a working man´s uprising of limited means.

Farmers and students in the countryside sell their belongings to raise the $2,000 required for an AK-47 smuggled from Iraq and to pay $4 for each round of ammunition. But bullets are as much use as a catapult against a T72. "Until the big cities help us we will scrape along for ways to fight this revolution," said Hussein al-Brahim, an activist from Saraqeb. "But Aleppo businessmen don´t want to get involved. They cannot be anti-Assad because he gave them everything."

For those on the receiving end, the smoke and chaos that engulfed Saraqeb last weekend disguised the well-drilled military procedure that was under way. It has been honed during sieges of other rebel hotspots, from Homs and Deraa to Idlib city and other towns across the province. The tanks go in first, shelling rebel positions and driving them out. The next day, there is random shellfire to soften the target. Then, once every rebel - and foreign journalist - has left, the ground forces go in. This way, there are few witnesses to what happens next.

The accounts of atrocities committed when Syrian ground forces move are impossible to verify, but the numbers hurt and arrested are unquestionably high.

Using information stored on laptops, army intelligence officers detain all manner of people. Bad-mouthing the regime? Arrested. Seen at a protest? Arrested. Got an internet connection? Arrested. The list goes on.

"The shabiha (pro-government militia) came to my house and took my children," said Fatoum Haj Housin, a resident of the town Sarmin, five miles north-west of Saraqeb, which had been attacked a few days earlier.

"They took all three of them. They were young men in the army but they defected in January. The militia shot them in the head and burned their bodies in front of me in our courtyard. In the name of God, bring me a Kalashnikov and I will kill Assad myself!"

There was still scorching and ash in front of her house - and much evidence elsewhere in Sarmin of destruction by ground forces. The field hospital had been torched, walls and houses sprayed with AK47 fire and the mosque smashed by three shells.

When the tanks leave the city centres and the ground forces come in, this is what happens - with nobody from the outside to see.

Yet for every person killed the rebels´ resolve seems to grow day by day.

"We can never go back now," said Feras Mulheen, a student from Saraqeb who had just seen his house destroyed by the tanks. "There´s nothing to go back to. We either win or we die trying. There´s nothing in between." * John Cantlie is an independent photojournalist (© Copyright of Telegraph Media Group Limited 2012. 04/01/12)