New Delhi: In yet another hiccup, security agencies could not complete the lockdown of all the Commonwealth Games venues and the Village on Saturday midnight as work was still in progress at some of the sites, even as they operationalised exclusive lanes on important roads to facilitate Games-related traffic.

Also on Sunday, two more Australian athletes pulled out from the October 3-14 event citing security and health concerns. Cyclist Travis Meyer and table tennis player Stephanie Sang had withdrawn from the event, Australian Associated Press reported.

Speaking about the slippages in the security lockdown, a Delhi Police officer said: "Work is still on at the Games main venue Jawaharlal Nehru Stadium, the Games Village and some other venues. We have been told that the Jawaharlal Nehru Stadium will be handed over to us by Sunday night and the Games Village by Monday."

Home Minister P Chidambaram had, on Septmeber 23, asked the Games Organising Committee to complete all work at venues by Friday night and hand them over to the Delhi Police for the lockdown.

The police had earlier decided on a complete security lockdown a month before the October 3-14 event. The lockdown was then planned from September 15 but it was extended to Wednesday midnight.

The Delhi Police said all security measures are in place and roads leading to Games venues and Village have been barricaded. Unmanned aerial vehicles (UAVs) had been put in place to keep an eye from the sky on the venues and to guard against any airborne attack.

Four-tier security is now in place at the venues and the Games Village. Only those with authorised passes will be allowed into the restricted areas.

Around 85,000 policemen in uniform and plain clothes, and 20,000 paramilitary commandos will be deployed in and around the Games stadia.

After attending a meeting with Prime Minister Manmohan Singh on Thursday, Delhi Police Commissioner YS Dadwal had said: "I assure international athletes that there is fool-proof security for the Commonwealth Games. There is no doubt about it."

The Commonwealth Games Organising Committee has faced criticism from officials of various countries over the alleged lax attitude of officials involved in preparations for the Games.

According to Satyendra Garg, joint commissioner of police, (Traffic), the exclusive lanes will be from the Games Village, NH 24, Ring Road up to the Barapullah flyover, 4th Avenue, Lodhi Road, Safdarjung Road, Kamal Ataturk Marg and Panchsheel Marg.

"These Games lanes will be maintained up to Oct 16," said Garg.

He said public will be able to use the dedicated lanes on other stretches for their movement except for the time when there is Games related movement.

"A traffic motorcycle blowing siren and traffic staff at intersections will intimate people about the movement of Games-related traffic. At the time of movement, people are expected to give precedence to Games traffic even on the roads where an exclusive Games lane is not operational at that time," he said.

Though the route from the Games Village to competition venues and the airport has a dedicated lane, there will be no such facility for practice venues.

The official said there would be no special lanes for roads leading to practice venues but motorcycle patrols would lead the convoys of athletes.

These restrictions are not applicable to Delhi Police vehicles, ambulances, fire tenders and other emergency services vehicles.

Commenting on the withdrawal of the Australian athletes, the country's Commonwealth Games chief Perry Crosswhite said he was disappointed that it had happened just a week from the start of the event but respected the athletes' decisions.

"I am disappointed on the basis that these Games will be a good experience particularly for all the athletes who come to it and of course we wouldn't be here if we didn't think the security was not being organised well and at the level it should be," Crosswhite said.

Crosswhite said the recently-married Sang pulled out because of security fears, and a replacement for her on the team was being sought.

Meyer, who is in Switzerland with the Australian team, was more concerned about health issues, including dengue fever, and had opted to miss the event and compete with his professional team instead.

Travis' brother Cameron Meyer will remain on the team in Delhi.

Australia's athletes will begin arriving in Delhi from Monday morning.

Some 7,000 participants and officials from 71 teams are expected to attend the Commonwealth Games, India's biggest sporting event since the 1982 Asian Games.