MAIDUGURI, Nigeria: More than 300 children and staff are thought to have been abducted from a Catholic school in Nigeria this week, one of the worst mass kidnappings ever recorded there.

The Christian Association of Nigeria said on Saturday it had raised its estimate of those taken from St. Mary’s School in Niger state on Friday to 315, up from an earlier estimate of 227, following a “verification exercise.”

“This now makes it 303 students (and) ... 12 teachers, bringing the total number of abducted people to 315,” it said in a statement, adding the new figure included 88 students who had been captured as they tried to escape.

The kidnapping comes amid a surge of attacks by armed groups and insurgents in Nigeria,

If confirmed, the revised number of people taken at the school would exceed the 276 schoolgirls abducted by Boko Haram militants in Chibok in 2014.