A 50-kilo stone was used yesterday to smash the windscreen of a car rented by the Committee Against Bird Slaughter and parked by the roadside in Delimara as the group's members patrolled the area.

The incident took place in the early hours when two CABS teams, in the company of police officers from the Administrative Law Enforcement unit, were investigating reports of illegal hunting and trapping in the area. No one was injured.

CABS spokesman Axel Hirschfeld said: "We can only assume that this cowardly attack is an act of revenge on the part of bird poachers."

CABS bird guards on Wednesday recorded about 300 shots at birds of prey and turtle doves to the east of Delimara. Police units alerted by CABS arrested two alleged poachers.

The conservationists said yesterday they had filmed a poacher with a weapon in his hand and caught a quail trapper red-handed in the same area. The ALE is investigating both cases.

The attack on the vehicle being used as a patrol car by CABS is the latest in a series of violent acts against bird conservationists. At the beginning of last week, the rear window of a BirdLife Malta vehicle was shattered by a shotgun blast. Just a few days later, a foreign bird protection team was attacked and an Italian birdwatcher was knocked to the ground.

Near Mtaħleb, graffiti consisting of anti-German slogans and bird symbols were found, including the threat: "You Germans will pay for this".

CABS is a German conservation organisation present in Malta to monitor the spring hunting season.