Struggling to retain their last bit of territory in the north, Tamil Tigers struck back with vengeance on Tuesday when one of their suicide bombers killed at least 15 people and injured more than 20 others, including a senior minister, outside a mosque in southern Sri Lanka [Images].

Postal Services Minister Mahinda Wijesekara, who is reportedly battling for his life, was airlifted to Colombo for emergency treatment.

Former southern province Chief Minister H G Sirisena was also injured in the attack. "Around 10-15 people were killed as the suicide bomber struck the celebrations outside the mosque at Matara. A lot of people were blown to pieces, which is making the death count difficult," Matara police spokesman Ranjit Gunasekara said.

The bomber appeared to have targeted six ministers and local politicians as they walked in a procession towards a mosque in Akuressa area in Matara to mark Milad-ud-Nabi, the birth anniversary of Prophet Mohammad. The attack came at a time when the Sri Lankan forces are on the verge of rooting out the LTTE [Images] from their last territory in Wanni region after 25 years of ethnic conflict.

The audacious strike showed that the Tigers still retained some capability to launch attacks far from their traditional strongholds in the north and east. Military spokesman Brigadier Udaya Nanayakkara said the blast was a suicide bomb attack and was carried out by the Liberation Tigers of Tamil Eelam.

The Tamil Tigers have repeatedly targeted senior government ministers and officials for assassinations and have been blamed for more than 100 suicide attacks. The latest suicide bombing came as more than 250 LTTE rebels were killed in intense battles, which have been raging over the past few days near Pudukudiyyiruppu coastal region, in Mullaitivu district.

The pro-LTTE website TamilNet.com said at least 100 government troops had been killed in the battle. It said 74 civilians have been killed and hundreds others injured on Monday and today in Sri Lankan shelling of Tamil-controlled areas.