Officials from Japan’s top police agency began their probe into security lapses blamed for former Japanese Prime Minister Shinzo Abe’s assassination a week ago Friday in western Japan, where people brought flowers to pray for the influential but divisive former leader.

Mourners carrying bouquets stood in a long line Friday to lay flowers and pray at a table outside of a railway station in Nara in western Japan. Some observed a moment of silence in the late morning around the same time the suspect fatally shot the country’s longest-serving prime minister, whose ultra-conservative stances on security and wartime history have divided views in and outside Japan.

A team of National Police Agency investigators on Friday inspected the shooting site, a day after Prime Minister Fumio Kishida blamed “problems with the security measures” for the death of Abe.

Photos and videos of the shooting show the alleged gunman was able to approach Abe from behind, while security guards were focused on the front.

Tomoaki Onizuka, head of Nara’s prefectural police headquarters, also prayed for Abe on Friday and inspected several bullets that had penetrated the wall of a nearby building, apparently after narrowly missing the former leader or anyone else in the area, officials said. Onizuka has said security problems during the attack were “undeniable.”