With just four days to go for the Commonwealth Games here, Home Minister P. Chidambaram on Tuesday reviewed the security arrangements with top officials.
Delhi Police have stepped up vigil by cautioning the public against hidden explosive materials in public places.
Home ministry officials described Chidambaram's meeting as a "routine internal meeting".
"The security scenario in the city and across the country in the run-up to the Games was reviewed again. Plans for the 'Games mode' security, likely to begin October 1, was finalised," a senior official told IANS.
The meeting was attended by Home Secretary G.K. Pillai, chiefs of the Intelligence Bureau, Research and Analysis Wing and other security agencies and senior ministry officials dealing with the CWG security and internal-security, sources said.
After the meeting, Chidambaram took a round of the 24X7 control room for the Games, set up in the North Block building itself, they added.
The Delhi Police made announcements through the public address systems at bus stations, market places and railway stations asking people to be vigilant about any hidden explosive materials in public places.
"Our bags and luggage were checked by the police," Ram Narain Meena, a passenger who arrived at Sarai Kale Khan bus station from Alwar, told IANS.
As the police enforced the CWG exclusive lane travel system for the Games participants and personnel, commuters were delayed in several localities in the city.
"The delays are increasing on National Highway 24 near the Games Village day by day. I took 80 minutes instead of the usual 40 minutes for a 20-km car journey from Ghazipur to Gole Market," said Ravi Shankar, an employee of a private firm.
Since Monday, Unmanned Aerial Vehicles (UAVs) were deployed in Delhi skies to detect aerial intrusions as Army helicopters hovered over the Games Village to provide protection to the 63-hectare campus, which has begun to house athletes for the Games to be held Oct 3-14.
About 7,000 athletes and officials from 71 countries and territories will participate in the CWG, the biggest sports event to be hosted by India since the 1982 Asian Games.