An 18-month-old boy is in critical condition at a Minneapolis hospital Tuesday and a person who was looking after him is in custody.

Police in Braham, Minn., were called to the 200 block of Beechwood Avenue S. about 1 p.m. Monday on a report of a child “in medical distress,” Police Chief Eric Baumgart said.

Officers administered first aid until paramedics arrived. The child was then taken to Minneapolis Children’s Hospital with “grave injuries,” Baumgart said.

Police interviewed the caregiver and found that the explanation for the child’s injuries “was not consistent with the severity of the injuries,” Baumgart said.

The caregiver was arrested.

No other details have been released.