Three airlines have cancelled or changed flights to Sri Lanka after Tamil Tiger rebels carried out an air raid on the capital, Colombo.
Sri Lankan officials say little damage was caused by the attack
Hong Kong airline Cathay Pacific and Dubai-based Emirates have suspended flights, while Singapore Airlines will only fly into Colombo during the day.
Two fuel facilities and a gas storage depot were bombed in Sunday's attacks.
Meanwhile, 12 people were killed in two clashes between Sri Lankan forces and the Tigers on Sunday, officials said.
A statement by the defence ministry said six people, including five rebels, died when troops stormed a Hindu temple on a small island off the northern Jaffna peninsula.
The custodian of the Amman temple was the sixth person killed in the raid.
In a separate clash, six rebels were killed by government troops in the north-eastern Weli Oya region, the government said.
The Tamil Tigers have not yet commented on the incidents.
In other violence on Sunday, a young reporter working for the Tamil newspaper Uthayan was gunned down on his bicycle near his office in Jaffna.
Selvarajah Rajivarnam, 25, was the second journalist killed in a government-controlled area in the past 10 days.
The media watchdog group, Reporters Without Borders, condemned the murder and called on the authorities to identify and punish those responsible.
Following Sunday's air raid - the third carried out by the Tamil Tigers using light aircraft in the last month - a number of international airlines flying to Sri Lanka reviewed their operations.
Singapore Airlines announced it would only fly into Colombo's Bandaranaike International Airport (BIA), which shares a runway with the Sri Lankan air force, during daylight hours.
"As a security precaution, with regard to the extenuating circumstances in Colombo, we have rescheduled our flight departure and arrival times," the airline told the AFP news agency.
"It will be a daytime flight instead of a night flight."
Emirates and Cathay Pacific, meanwhile, said they would suspend flights until further notice.
"Safety is a top priority at Cathay Pacific and a careful assessment of the situation will be made before services are resumed," the Hong Kong-based carrier said.
Cathay Pacific halted flights for a week in the wake of the rebels' first air attack a month ago, which killed three air force personnel and injured 16 others.
A second aerial bombing, of a northern military complex last Tuesday, killed six soldiers.
Tourists 'not endangered'
The airlines' announcements come despite assurances from the Sri Lankan government that the military is capable of dealing with the Tamil Tigers' air threat.
The Tamil Tigers may have up to five planes, experts say
The Sri Lanka Tourist Board issued a statement on Monday which stressed that Sunday's attack had caused little damage and that the country remained a safe place for tourists.
"In the two decades of problems, mainly confined to the north-east of the country, no foreigner has been targeted," it said.
"In the recent past the targets have been military and political, thus not endangering tourists."
But a spokesman for the Tamil Tigers warned there would be further air raids.
"The Sri Lankan military, especially the air force, are adamantly trying to prove they will always seek a military solution," Rasiah Ilanthiraiyan told Reuters.
"So we have no other way than to take our own measures."
"There will definitely be more. We have no choice other than striking back."
The Liberation Tigers of Tamil Eelam (LTTE) are fighting for a Tamil homeland in the north and east of the country.
More than 64,000 people have died since the civil war began in the early 1980s.