An Israeli policeman has been arrested on suspicion of selling ammunition to Palestinians, police said Thursday, raising to ten the number of suspects detained in the case. 

The latest suspect, Eran Mulai, lives in a Jewish settlement enclave in the West Bank, as did others already arrested in the same case, police spokesman Rafi Yaffe said. 

Police have said that they believe the suspects sold some 50,000 bullets for M-16 automatic rifles to members of the Tanzim, a militant Palestinian group. Israel blames the group for dozens of lethal attacks, including many shootings that have targeted Jewish settlers. 

Mulai is from Hebron, a city where about 500 Jewish settlers live, surrounded by more than 100,000 Palestinians. 

Several of the other suspects are from the nearby Adora, a settlement that came under attack by Palestinian militants on April 27. The gunmen shot dead four residents, including a 5-year-old girl. 

Mulai was doing his three years of compulsory military service in the police. Israeli men serve for three years in the army, from the age of 18, but some have the option of serving in the police instead. 

The other suspects are also current or former members of the security forces. 

In all, police said they were holding three suspects, while the army said it had detained seven. 

Two Palestinians, one from Hebron, the other from nearby Tarqumiye, have been arrested on suspicion of buying the ammunition. Police said the investigation was ongoing and none of the suspects has yet been charged.