A 25-year-old member of the Vatican's elite police force died on Monday of gunshot wounds in an apparent suicide case, the Vatican said.

It was the worst incident of violence inside the Vatican since a triple murder-suicide in 1998, when a member of the Swiss Guard killed his commandant and his commandant's wife and then turned his gun on himself.

Alessandro Benedetti was found in a bathroom in the barracks of the Vatican Gendarmes with gunshot wounds in the early hours of Monday and rushed to a nearby hospital, where he died 1-1/2 hours later.

"The first indications are that the young man committed suicide," said a Vatican statement, adding that Benedetti had left a note which was with Vatican investigators. The statement offered no details about possible motives.

Benedetti joined the Gendarmes, who are in charge of the Vatican's security in which they are assisted by the largely ceremonial Swiss Guards, as a trainee in April.

"His behaviour had not previously given cause for concern", the Vatican said.

The Vatican said the selection process for the Gendarmes, who are recruited in Italy unlike the Swiss Guards, includes psychological screening for aptitude for firearms.

"The Holy Father (Pope Benedict) was grieved to hear this news and entrusts young Alessandro to God's mercy," said the Vatican.

In 1998, Swiss Guard Cedric Tornay shot dead commandant Alois Estermann and his wife and then shot himself, in what the Vatican termed a "fit of insanity" for being passed over for promotion. Tornay's family has contested that version.