Colombo, Nov 20 (IANS) The security situation in Sri Lanka has improved since the defeat of the Tamil Tigers but Americans travelling to the country should remain careful, the US said Friday.

'The Department of State warns US citizens about the risks of travel to Sri Lanka due to continued security concerns, especially in the northernmost areas and most of its Eastern Province as there are still uncleared landmines and potential for incidents by remnant members of the Liberation Tigers of Tamil Eelam (LTTE),' a travel advisory said.

But it added that stability in the Sinhalese-majority southern and western areas of the country had improved with the cessation of hostilities.

'The Department of State urges US citizens to remain vigilant while traveling in Sri Lanka,' it said.

'US citizens are advised to defer all travel to the Northern Province,' it added, referring to the region where the military crushed the LTTE and decimated its leadership in May.

The advisory pointed out that Sri Lankan authorities continue to find hidden caches of military grade weapons.

'US citizens are advised against travel on public buses in Sri Lanka as they were previously targets of LTTE bomb attacks and remain targets of criminal activity...

'Demonstrations at or near Western embassies have also increased in frequency, often with inadequate police response for crowd control.'