It was a long vigil in a city they were unfamiliar with.
But the task for the Delhi police's special team was to track down Sher Singh Rana, main accused in the assassination of Phoolan Devi, who had walked out of Delhi's high-security Tihar jail in a daring escape, dressed as a policeman.
Sniffing around different parts of the country, the trail had led the team to West Bengal and, finally, to Calcutta. But the brief was also to keep the Calcutta police out of the picture, a task that the team from the capital achieved with remarkable ease.
The groundwork had started last December, when officers from Delhi police had come to the city to carry out a recce. It had taken them to Basirhat, in North 24 Parganas.
It was only early this month that some 'concrete' information about the possible arrival of Rana in Calcutta reached the Delhi police and they decided to send their men across.
The first to arrive was Ranbir Singh Dahiya, an officer of the special team, who reached the city on April 21. The only information he had was that Rana was in Bangladesh and his visa was about to expire.
'We had definite information that he was coming to Calcutta and that is why we decided that we would set up a vigil for him and wait till he appeared on the scene,' said Karnal Singh, joint commissioner of Delhi police's special cell.
'We also had information that he would be staying in a hotel in central Calcutta. It was not an easy task, but let us say that we were helped by certain people who were passing on information to us. It is not possible to reveal anything further,' he added.
Dahiya checked into a hotel on Sudder Street, but did not mention any address or telephone number in the register. Then, he activated his contacts and the search began.
But the task was simply too much for him alone and two days later, he was joined by two other officers, Surinder Kumar and Satyabir Singh.
They checked into the same hotel and maintained the same anonymity. Only, in the address space in the hotel register, they added the words Lodhi Colony.
The trio then found out ' again from their sources ' that Rana had arrived in the city and was using a satellite phone. With the help of the telecom authorities, they learnt that Rana was in the Dharamtala area.
'Being unfamiliar with the city, it was difficult for them to go about tracking hotels and positions,' said a senior officer of Delhi police.
So, the team in Calcutta once again contacted their bosses in Delhi, saying that the 'Dharamtala area' was proving too big for them and requested reinforcements.
On Sunday, eight other officers arrived. The search narrowed down and on Monday evening, the Delhi police found their quarry in a phone booth near Metro cinema.