Diamond Harbour, Aug. 6: Two murderers and a couple of dacoits today cocked a snook at prison security and cut a grille, climbed roofs and scaled walls to flee.

Diamond harbour sub-jail realised that the four were missing during the daily roll call around 7 in the morning. The alarm was rung.

Vegetable vendors in Baruipur, 30km away, caught one of them. Ironically, even before the police realised that the goons had fled.

The vegetable sellers saw the four around 4am and smelt something fishy. But they could only latch on to murder convict Sheikh Motaleb.

Police said Azim Mistry and Motaleb were picked up in April 2006 in connection with the murder of a Sarisha Ramakrishna Mission student. Subhas Biswas and Abdul Mannan, said to be Bangladeshis, were rounded up after a heist in Kakdwip in 2005.

A preliminary probe has revealed that they sawed off a rusted window grille in their ward. “Azim is believed to have got the saw in through his wife,” said S.R. Hossain, the deputy inspector-general of prisons (security).

Hossain, who visited the jail, said the warders couldn’t disown their responsibility. “How could an inmate manage to get a saw inside without the warders’ knowledge?” he asked.

The century-old jail has over 350 inmates and 18 warders oversee the security round the clock.

“We have identified some of the warders and all of them would be under suspension until the probe is completed,” Hossain said. A jail inmate told police the four came out of their ward through the broken widow. They are then believed to have climbed the tin-roofed kitchen adjoining the ward. From there, the roof of a room where convicts are kept before being assigned a cell.

The prison wall may be 18ft high, but it is only 2feet from the roof. Beneath it — on the outer side — is a shrub cover.

“They must have slipped out between 1am and 3am,” Hossain said.

South 24-Parganas superintendent of police Praveen Kumar said the quartet were spotted near Baruipur railway station around 3.45am, when vegetable sellers from the area head to Sealdah and other Calcutta markets.