Passengers will be prohibited from carrying unpacked knives on trains as part of new security measures sparked by last month’s attack in a bullet train, the transport ministry said.

The measures, announced Friday, allow station staff and conductors to forcibly evict passengers found carrying knives on all trains.

The measures, however, will not require baggage screening, as that would require extra space and hamper the boarding process, the ministry said, raising the question of how effective the new security measures will actually be.

“We will implement measures to enhance security ahead of the Tokyo Olympics and Paralympics” in 2020, said Land, Infrastructure, Transport and Tourism Minister Keiichi Ishii at a news conference.

In proposals reported to the ministry, railways suggested arming their staff with shields, stab-proof vests and tear gas as new steps. They are also considering using smartphones and tablet computers to share security camera images inside trains.

The ministry has been considering measures to strengthen security since June 9, when a knife-wielding man in his 20s went berserk while riding a Nozomi bullet train from Tokyo to Shin-Osaka Station. The attacker killed a 38-year-old man who tried to stop him and injured two women in their 20s.

That incident follows a self-immolation carried out by an elderly man on a bullet train in 2015. The fire, however, ended up killing another passenger, which revived debate on how to balance convenience with safety.

Since last month’s incident, bullet train operators have increased the number of security guards and patrols conducted inside trains. They will also provide training for train crews and office staff on how to respond to emergency situations.