MILAN, Italy (AP) - Serie A leader Inter Milan has become the second Italian soccer team in two days to receive a threatening letter with bullets inside the envelope.

The unsigned letter, which arrived Friday, told Inter's chairman Massimo Moratti to be "very, very careful," the ANSA news agency reported. The letter also insulted and threatened Inter coach Roberto Mancini and striker Zlatan Ibrahimovic, who is tied for the league lead with 13 goals.

Police confirmed the existence of the threatening letter but would not discuss the content. An Inter spokesman declined to comment.

A similar unsigned letter arrived at the offices of AC Milan on Thursday in an envelope that contained a bullet. The letter threatened Milan president Silvio Berlusconi - the former Italian premier who is also the head of Italy's center-right opposition - as well as club vice president Adriano Galliani and coach Carlo Ancelotti.

A Milan spokesman said it was not the first time such a threat had been received, but he could not remember when the last one was.

Former Italian referee Pierluigi Collina - who now selects and trains match officials - has had a security detail since November. Collina received a threatening letter late last year that Italian officials deemed to be serious, news reports said.

i'm telling you, all this? it's Cap'n Jack! he hasn't been around since the confirmation of the first letter!

Yeah he hasn't showed up here for some time now...

maybe inter did it to us and we did it to inter like a little game