Tamil Tiger rebels have carried out an air raid on targets in and around Sri Lanka's capital, Colombo.
Residents say they heard at least two powerful blasts in Colombo
Two fuel facilities were bombed in what the rebels said was in response to an army strike on their positions.
One gas storage depot was set ablaze, officials said. It is not clear if there were any casualties.
Authorities turned off Colombo's power, as large crowds gathered to watch Sri Lanka play Australia in cricket's World Cup final.
One commercial airline, Cathay Pacific Airways of Hong Kong, has announced that it is suspending flights to Sri Lanka indefinitely.
It had only recently resumed flights there after halting them in the wake of the rebels' first air attack a month ago.
Hours after the attack, Sri Lankan Air Force jets pounded Tiger-held areas in an effort to destroy their aircraft.
During the raid on the capital, government troops fired anti-aircraft guns and cut power to Colombo, its airport and an adjoining army base.
The public had been warned to be on guard after the Tigers unveiled their own air power with two aerial bombings in the space of a month.
Tiger military spokesman Rasiah Ilanthirayan said that two squadrons of what he called the Tamil Eelam air force took part in the raid late at night.
He said two fuel facilities were bombed, and that the pilots returned safely after the mission.
The authorities said one gas storage facility was set ablaze in the raid, but the fire was quickly brought under control.
A state petroleum building was also hit, though the extent of the damage was not immediately known.
A Sri Lankan government minister later described the raid as failure.
Colombo residents said they heard at least two powerful explosions in the city.
"I heard terrible explosions and I saw red sparks flying upwards from the ground and I heard shooting," Josef Penkava told the BBC News website.
Many residents were watching the Sri Lankan national cricket team play Australia in the World Cup final when the army responded with anti-aircraft guns and the city was blacked out.
"We were watching the match when the lights went off. Within minutes the night sky was brightened with anti-aircraft fire," Shivantha Fernandopulle said.
"After about 30 minutes the firing ceased. After a lull of about an hour there was a second round of firing. A plane could be seen flying westwards towards the Indian Ocean."
There are no reports of damage following the air force raid into Tiger territory.
The BBC's Roland Buerk in Colombo said destroying the Tigers' aircraft and jungle airbases has become the number one priority of the Sri Lankan Air Force.
In March, the Tigers carried out their first aerial attack on the Colombo air base, killing three air force personnel and injuring 16 other people.
Rebels are believed to have smuggled light aircraft in pieces
The Tigers later released pictures of a plane - a two-seater Czech Zlin light aircraft adapted to carry bombs.
A second aerial bombing, of a northern military complex last Tuesday, killed six soldiers.
Last Thursday, Colombo's airport was shut down and anti-aircraft guns were fired after reports of unidentified aircraft approaching the capital. That incident proved to be a false alarm.
Experts say the Tigers could have as many as five light aircraft, smuggled into the country in pieces to be assembled in jungle bases.
Both the Tigers and the military are, officially, still observing a 2002 ceasefire which has become meaningless in practice.
Violence began to increase after the 2005 election of President Mahinda Rajapakse. Since then about 4,000 people have been killed.
The Tigers are fighting for a Tamil homeland in the north and east of the island.
More than 64,000 people have died since the civil war began in the early 1980s.