The search for a helicopter which disappeared in Italy with seven people on board intensified Friday after the weather improved, a spokesman for the Alpine rescue service told AFP.

The helicopter was carrying a pilot and six passengers -- four Lebanese nationals and two Turks, according to Italian media reports.

It went missing in a sparsely populated mountainous area in northern Italy Thursday, but bad weather hampered the first attempts to find it.

Seven helicopters from the air force, police and medical rescue services were combing the area Friday.

"It is not easy, if a helicopter falls amongst trees, in this season the branches close over it and it is complicated to see it from the sky," the spokesman said.