Authorities in Cyprus are investigating the destruction by poisoning of hundreds of trees on the Mediterranean island.

The forestry department called in police after finding evidence that pine trees lining two key motorways had been deliberately killed.

"We found that the lower parts of tree trunks had been pierced with a drill and herbicide was placed inside," George Pattichis, a forestry department spokesman, told Reuters.

"They are mainly pines and cannot be saved."

Cyprus is suffering its worst drought in decades, but the huge number of usually hardy pines wilting and dying made authorities suspect something else was afoot, Pattichis said.

A man was being questioned by police on Wednesday.

Newspapers reported the suspected motive was to offer drivers a clearer view of advertising billboards currently obstructed by the trees.