Four people have been detained after being caught trying to smuggle a Soviet AK-630 anti-aircraft cannon across the Polish-Ukrainian border, the Internal Security Agency (ABW) has said.

The AK-630, a six-barreled, 30mm naval anti-aircraft cannon, was found during an inspection of a Ukrainian-registered van at the Dorohusk border crossing in eastern Poland.

Two Ukrainian women who were in the car had claimed they were transporting plumbing equipment. They were both detained.

Further investigation was carried out at the delivery address and one other location. As a result, 1,300 packs of illegal cigarettes were seized, and another two Ukrainian citizens were detained.

All four detainees deny that they tried to smuggle military equipment, claiming not to have known it was a cannon.

In full operation, the cannon can shoot six 30-mm shells at a speed of 900 metres per second. (vb/rg)