Here’s what is known about the man suspected of murdering Shinzo Abe

Police have launched an investigation into the murder of former Japanese Prime Minister Shinzo Abe – but little is known about the suspect who was arrested at the scene of the case on Friday.

Tetsuya Yamagami, 41, admitted to shooting Abe, according to Nara Nishi police. He, who is unemployed, told investigators that he hates “a certain group” that he thought the politician was connected to. Police did not name the group.

The investigators reported that Yamagami responded calmly to the questions and showed no emotions as he spoke. Police confirmed that he served in the Japanese Navy for three years.

The suspect used a homemade gun in the shooting, authorities said, and footage from the scene showed what appeared to be a gun with two cylindrical metal barrels wrapped in black tape. Later, several handcrafted pistol-like items were confiscated from Yamagami’s apartment.

The object was 40 centimeters long and 20 centimeters wide, police said.

Yamagami made various types of weapons from iron tubes wrapped in duct tape, Japanese public broadcaster NHK reported, citing security forces. Police found weapons with three, five and six iron barrels.

The suspect inserted bullets into the barrel, for which he purchased parts online, according to the broadcaster citing police. Investigators believe he used the strongest weapon he did in the murder, NHK added.

Japan’s National Police Agency said it would review security arrangements put in place prior to the assassination, NHK said. Security was being handled by Nara Prefectural Police, who drew up a plan for the former prime minister while he was in the city.

The agency said several dozen police officers and agents from the Tokyo Metropolitan Police were on duty and reportedly watched Abe from all sides during his speech.