Calcutta police have raided Gopal Tiwari's home for the attack on cops at Girish Park after the civic polls, but only after giving him 72 hours to escape.

The attempt to round up the Burrabazar don drew a blank, strengthening allegations that the police are half-hearted about bringing him to book.

A team of the anti-rowdy squad of the detective department, along with officers of the local Jorabagan police station, reached Tiwari's home in Pathuriaghata on Tuesday night, only to be told that he was not in.

Sources said Tiwari's wife and two children told the cops that they were in the dark about where he could be found.

The six men who have been arrested in connection with the Girish Park attack, in which sub-inspector Jagannath Mandal took a bullet in his chest, are known in the area as Tiwari's men, investigators and residents have said.

In the days leading to the Calcutta Municipal Corporation elections on April 18, Tiwari was allegedly seen roaming the area with the accused and also Trinamul leader Sanjay Bakshi, whose wife Smita is the local councillor (Ward 25) and an MLA.

Police sources said Tiwari was a key link between the goons who carried out the attack and the local Trinamul leaders under whose instructions they were acting.

Within hours of the attack on Saturday, the police had tracked down Tiwari to a Trinamul office in the Girish Park area but decided against arresting him after realising that he was with Smita Bakshi. The MLA has denied the allegation.

The arrested men, in police custody since Sunday, have named Tiwari as the person who had sent them to Singhibagan, where the policemen came under attack, for "area domination", the sources said.

Till Tuesday evening, the top brass of the detective department, which is investigating the attack, refused to officially identify Tiwari as a suspect in the case.

When asked on Tuesday evening whether Tiwari was on their radar, joint commissioner (crime) Pallab Kanti Ghosh said: "I cannot answer this question."

But soon after, the official confirmation came - through action. "We raided Gopal Tiwari's house but could not find him," a senior officer in the detective department said on Tuesday night.

The instruction to "act", according to sources, came from the highest level of Calcutta police after three days of alleged indecision.

Sources at Lalbazar who were kept in the loop about the developments related to the raid told Metro that the raiding team went to Tiwari's home and then to some other places in the locality before returning to the police headquarters.

"Though his wife refused to share any information, neighbours said Tiwari was often seen in the local Trinamul office," an officer said.

The officer, however, refused to say whether the anti-rowdy squad cops visited the local party office.

Senior investigators said Tiwari had enough time since the day of violence - 72 hours - to weigh his options and sneak out of Bengal.

On Monday, he had spoken to The Telegraph from an undisclosed location. Had he been on the police radar in the case since the beginning, the sleuths could have reached him by tracking his cell phone.

Tiwari's phone is switched off since late on Monday. "It is clear he got an indication that police would now go after him. So he switched off his phone. Before that there was no need for him to hide," said a resident of central Calcutta who has known Tiwari for years.

Tiwari was sentenced to life by the Bankshall court for trying to kill a tea-seller after taking money from Haldiram's owner Prabhu Shankar Agarwal in 2005. He got bail in the Supreme Court in 2012.

Cop better

Sub-inspector Jaganath Mandal's health improved on Tuesday but he remained in the intensive care unit at CMRI, hospital sources said on Tuesday. Mandal had undergone a surgery on Sunday to remove the bullet lodged in his chest.

"He had a normal diet of rice and fish and is speaking to guests," a hospital source said on Tuesday. "His vital parameters are stable, which is a good sign."