NET
27 When the jailer woke up and saw the doors of the prison standing open, he drew his sword and was about to kill himself, because he assumed the prisoners had escaped.
Darby
27 And the jailor being awakened out of his sleep, and seeing the doors of the prison opened, having drawn a sword was going to kill himself, thinking the prisoners had fled.
KJV
27 And the keeper of the prison awaking out of his sleep, and seeing the prison doors open, he drew out his sword, and would have killed himself, supposing that the prisoners had been fled.