The Sri Lankan authorities have installed anti-aircraft guns at the national parliament in Colombo.

The move follows reports that the separatist Tamil Tiger rebels may have acquired light aircraft that could be used for aerial attacks.

Visitors to the Sri Lankan parliament are already thoroughly searched, and there is a ban on vehicles entering the complex.

The Tamil Tigers have made a number of spectacular suicide bomb attacks in the capital and elsewhere during their fifteen-year campaign for an independent homeland.

Security has been tightened throughout Sri Lanka as the Tigers mark a week of remembrance of their members killed in the fighting.