Colombo (PTI): In a further blow to the air attack capability of the Tamil Tigers, Sri Lankan troops on Tuesday captured the seventh and last jungle airstrip used by the rebel outfit to launch strikes across the island but are still to trace any of the LTTE planes.

The 50-metre wide and two-km long runway, along with a hangar for light aircraft, were seized by advancing security forces in Puthukudirippu in Mullaitivu, officials said.

During the course of the heavy fighting over the last few weeks which witnessed the cornered rebels steadily losing territory, government troops seized six runways used by the air wing of the Liberation Tigers of Tamil Eelam.

However, they are yet to come across any of the Czech-made Zlin-143 single-engine planes believed to be used by the LTTE, prompting the authorities to order a strict vigil to prevent any air raid by the rebels on the country's independence day tomorrow.

The Tigers are believed to have four or five Czech-built light planes, smuggled onto the island in pieces and re-assembled. Defence experts do not rule out the possibility of Tigers dismantling the planes and whisking them away.

Some of the officials also believe that the LTTE is capable of using highways for take-off of their planes.

The LTTE "air force" came into prominence when it struck on the Sri Lankan military air base inside Colombo's international airport in March, 2007.

The latest air attack by LTTE took place in November last year when an LTTE mini-aircraft dropped two low-intensity bombs at a power station in Colombo.

This was preceded by an attack by an LTTE aircraft on an army camp in Mannar in October.