Postal deliveries have been suspended at a housing estate in Tallaght in west Dublin.
An Post says the decision was taken as a last resort, following ongoing threats to its staff.
People living in the Mac Uilliam Estate will have to collect their post until further notice.
"It's a serious development. I think it requires a garda response," said local TD Sean Crowe, adding that a meeting is planned to try and resolve the situation
"(I) met with the garda authority today and they have agreed that they would follow up with a meeting with An Post to try and resolve the safety issues in the area."