The Calgary Fire Department is reminding people not to go into the city's storm drain system after a group of eight kids went exploring Thursday afternoon and thought one of them got lost inside.

Fire crews were called to the 4900 block of 53rd Street N.W. about 2 p.m. by the kids themselves after they discovered one member of the group was missing when they came back out.

After some searching, it turned out the youngster thought lost wasn’t in the storm drain system after all, but had gone home.

A release from the city says the children were able to access the storm drain system as a manhole cover had been removed. Fire fighters at the scene were told the kids had been going inside the drain "with regular frequency throughout the week."

The city’s water works department is now taking a look at the area to see if there is a way to make it safer.

Calgary fire spokesperson Carol Henke said no-one should go into a storm drain unless authorized.