YEREVAN, Armenia (AP) — Authorities in Ukraine are investigating an outbreak of sickness believed to be a poisoning that sent 50 students and two teachers to the hospital in the city of Cherkassy.

A spokeswoman for the emergencies ministry, Olga Kozak, told The Associated Press that 11 of the children were in moderately serious condition while the other children and the teachers were in satisfactory condition.

The Tuesday outbreak at the school 190 kilometers (110 miles) south of the capital of Kiev caused some students to lose consciousness.

Prime Minister Volodymyr Groisman has flown to the city to direct the medical investigation.