A British woman is considering removing her sons from their primary school after one of them was allowed to leave unchallenged in the middle of the day and walk three-quarters of a mile home, crossing busy streets, the Daily Mail reported Thursday.

Tyler McGuire told his teacher he was going to the bathroom, but walked home instead. He was not hurt, but his mother Sara, says he was left vulnerable to danger.

School officials told the Daily Mail they were shocked by the “unfortunate incident” and have since installed a locked gate on the property.

“I felt sick when I found out what had happened. He should not be able to get out of school that easily,” McGuire told the Daily Mail. “You expect your children to be safe at school.”

Ashleigh Primary School teacher Mark Henderson said students’ safety is of the utmost importance, but within reason.

“Schools are not prisons and if the security of children is too intense it would not be conducive to learning,” he told the Daily Mail.

Click here to read more on this story from the Daily Mail.