The police on Saturday arrested the owner of the boat that was involved in the mishap near Thattekad Bird Sanctuary that killed 15 students and three teachers.
Raju, who was absconding after the mishap on February 20, was arrested from his wife's house at nearby Kothamangalam, police said.
A case under Section 301 (culpable homicide not amounting to murder) of the Indian Penal Code has been registered against him.
The students and teachers of the St Antony's UP School at Elavoor in the district were on an excursion to the bird sanctuary on Tuesday and were taking a boat ride near a reservoir when the mishap occurred.
