Stupid hijack ever

Egypt Air Flight MS181 carrying 56 passenger along with 26 foreign passenger was hijacked by a passenger claiming to be wearing a suicide belt. The motives of hijack is still unclear but it clearly seems not related to any

terrorism activities. All the passenger of the plane is unharmed.
How case is solved?

The morning was full of tension until the hijacker was seen walking down the aircraft steps Larnaca airport with his hands raised. Thanks god the man who hijacked the plane was fake but it arose the question in aviation security. Earlier in October Egypt was involved in similar activity letting someone smuggle explosive on  airliner destroying a Russian passenger jet in mid-air.

Local media reports said the hijacker had handed over a four-page letter in Arabic afterthe plane landed at Larnaca on Tuesday morning, and that later a woman thought to be his wife had arrived at the airport. Some reports said the Egyptian man - named by Cypriot officials as Seif Eldin Mustafa - wanted to talk to his Cypriot wife who lives on the Mediterranean island, while others said he was seeking the release of female prisoners in Egypt. Earlier, Cypriot President Nicos Anastasiades had responded to a reporter's question about whether the hijacker was motivated by romance, by laughing and saying: "Always there is a woman involved."
Major Question:

But question remains how a passenger as described by Cypriot authorities as  "mentally unstable"  was able to carry enough materials through airport to resemble a bomb?
Similarly what should be done to stop any future airline passenger, similarly unarmed but appears to be straped with bomb.?