The government has warned Britons that the risk of travel in Sri Lanka is increasing following the latest bomb attack in the capital, Colombo.

In the latest of a series of travel warnings issued by the Foreign and Commonwealth Office (FCO), the overall level of travel advice is unchanged.

But in a specific statement, the FCO adds: "There is an increasing risk of British nationals being caught up in an attack."

The tone of advice is unusual, as the FCO advice is normally couched in general terms. But the attack on Colombo's train station at the weekend has heightened fears that tourists may become accidental victims of the Tamil Tiger campaign.

A female suicide bomber killed 11 and injured more than 100 when she blew herself up on a crowded station platform. The station is used by tens of thousands of tourists noramlly heading for Kandy.

In what is suspected to be the latest stage of a separatist campaign by Tamil Tiger rebels, bombs were also exploded on a bus in the north eastern town of Weli-oya, killing 12 and on a second bus in the central Sri Lankan town of Dambulla on Saturday, which killed at least 18.

Britain today called for a ’political process’ to end the bloodshed. Foreign Secretary David Miliband in a statement said that the Sri Lankan government’s unilateral withdrawal from a ceasefire with separatist rebels did not mean both parties should stop protecting civilians.

“Violence can never provide an answer to Sri Lanka’s problems,” Miliband said.“A sustainable solution to Sri Lanka’s conflict can only emerge through a just political process involving all communities."

The FCO current travel advice in full reads:

"There is a high threat from terrorism in Sri Lanka. In 2008 fatal attacks have become more frequent. They have occurred in Colombo and throughout Sri Lanka, including in places frequented by expatriate and foreign travellers.

Further attacks may occur at any time. There is an increasing risk of British nationals being caught up in an attack. See the Terrorism section of this advice for more details.

We advise against all travel to the north and east of Sri Lanka, and to Yala National Park and the areas around it.

For the purpose of this travel advice we consider the north to be all areas north of the A12 road (which runs from Puttalam in the west to Trincomalee in the east) including the Jaffna peninsula.

We consider the east to be the districts of Trincomalee and Batticaloa, as well as coastal areas of Ampara district east of the A25 and A27 roads. We define the areas around Yala National Park as those east of the A2 and south of the A4. See the Terrorism and Local Travel sections of this advice for more details.

There is heightened security in Sri Lanka and you are advised to comply with government and security force instructions. There have been detentions particularly of people of Tamil ethnicity. You should ensure that you carry some form of official identification with you at all times. If you are detained, you should ask the authorities to contact the British High Commission.

We strongly recommend that all British nationals who are resident and/or working in Sri Lanka, or visiting for over one month, should register with the British High Commission in Colombo.

About 90,000 British nationals visit Sri Lanka each year (source: Sri Lanka tourism board). The main type of incident for which British nationals required consular assistance in Sri Lanka in 2006 was for replacing lost or stolen passports and ill health.

We strongly recommend that you obtain comprehensive travel and medical insurance before travelling. You should check any exclusions, and that your policy covers you for all the activities you want to undertake. See the General (Insurance) section of this advice and Travel Insurance for more details."

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