Pakistani police arrested "some suspects" today in connection with the attack on Sri Lanka's cricket team.
Six police officers and a driver were killed and seven players were wounded in the assault, exposing Pakistan's inability to prevent terrorist attacks.
Lahore police chief Haji Habibur Rehman said today that authorities had detained the suspects.
He gave few details but indicated that none of those detained were the gunmen.
Up to 14 heavily armed and well-trained assailants sprayed the Sri Lankan bus with bullets and fired a rocket and a grenade as it travelled to a match against Pakistan in the eastern city of Lahore yesterday.
The ambush bore many similarities to last year's three-day hostage drama in the Indian financial capital of Mumbai.
Working in pairs, the attackers in Lahore carried walkie-talkies and backpacks stuffed with water, dried fruit and other high-energy food - a sign they anticipated a protracted siege and might have been planning to take the players hostage.
None of the gunmen was killed and all apparently escaped into the teeming city after a 15-minute gun battle with the convoy's security detail.
Besides the six police officers, a driver of a vehicle in the convoy was also killed. Seven Sri Lankan players, a Pakistani umpire and the team's British assistant coach, Paul Farbace, were wounded.
The bus was peppered with 25 bullet holes in the attack, among the highest-profile terrorist strikes on a sports team since the 1972 Munich Olympics, when Palestinian militants killed 11 Israeli athletes.
Pakistan's Punjab provincial government took out advertisements in newspapers today offering an £89,000 reward.
The ad showed two alleged attackers, one dressed in brown and the other blue, and both carrying backpacks and guns. The image was taken from TV footage of the event.
By targeting a much-loved sport in Pakistan and elsewhere in south Asia, the gunmen were certain to draw international attention to the government's inability to provide basic security as it battles against militants linked to al-Qa'ida and the Taliban and faces accusations that it is harbouring terrorists.
The attack ended Pakistan's hopes of hosting international cricket teams - or any high profile sports events - for months, if not years.
Even before yesterday, most cricket squads chose not to tour the country for security reasons. India and Australia cancelled tours, and New Zealand announced it was calling off its December tour.
The International Cricket Council said it would review Pakistan's status as co-host of the 2011 World Cup.
Authorities cancelled the Test match against Pakistan and a special flight carried the Sri Lanka team - including Thilan Samaraweera and Tharanga Paranavitana, who had been treated in hospital for bullet wounds - home, where the exhausted-looking players had an emotional private meeting with their families.
One of the players was taken from the airport to a hospital in Colombo.
Captain Mahela Jayawardene, who was cut on the foot in the attack, said: "I'm very happy that I could see my family, and come back to Sri Lanka in one piece. Every breath I take I'm glad that I can take it without a problem."
Sri Lankan foreign minister Rohitha Bogollagama flew to Pakistan to discuss the incident.
Pakistan has a web of Islamist militant networks, some with links to al-Qa'ida and the Taliban, which have staged other high-profile strikes to destabilise the government and punish it for its support of the US-led invasion of Afghanistan.