KUALA LUMPUR - Education Minister Mahdzir Khalid said the mass hysteria that broke out in several schools in Kelantan last month was caused by stress, anxiety and depression, news portal Malaysiakini reported on Wednesday (May 25).

Mass hysteria hit several secondary schools in Kota Baru, the capital of Kelantan state, last month, affecting more than 100 students and teachers and causing at least one school to be closed for three days.

In all the cases, the affected students claim that they saw "pocong", "pontianak" or other supernatural beings during the attacks. Doctors and religious figures were rushed to the schools to provide help and treatment.

"Tests conducted by medical experts have found that the students fell victim to hysteria due to serious chronic stress, anxiety and depression, as well as from being under pressure," Mahdzir said in response to a question from MP Sim Tze Tzin on the cause of the hysteria and how it could be avoided, Malaysiakini reported.

Mahdzir said the schools isolated the affected students and informed their parents. The Kelantan education department worked with the health department to conduct "emotional restoration programmes" for the affected students, he added according to Malaysiakini.

Discussions were also held with the parents and the local community to look for solutions, the minister said.

For the long term, the schools were told to seek "expert" help from religious leaders, psychiatrists and others, he said.