At least 18 students of two schools in Patharghata upazila under Barguna district became unconscious in the last three days. 

Of them, 16 students of Haritana Model High School and two of Taslima Memorial Academy in the upazila became unconscious after convulsions in their hands and feet while their classes were going on, our Bhola correspondent reports quoting Utpal Kumar Mitra, headmaster of Haritana Model High School.

"All the students are aged between 12 and 16 and were admitted at the Patharghata Upazila Health Complex as their condition deteriorated. Five students fell sick on Tuesday, eight on Wednesday and three on Thursday. Following the incident, we declared our school closed for four days," the headmaster also said.

The students were suffering from mass hysteria, the headmaster told our correspondent quoting Mostafijur Rahman Sajal, a doctor of the health complex.  

Two of them are being treated at the hospital at present, the rest are now out of danger, he added.

Ramesh Chandra, health and family welfare officer at the upazila, said that it is a case of mass hysteria and any mental pressure may cause such unconsciousness.

"Absence of proper sanitation system or pressure of studies may cause such illness," the health official added.