Published: Apr 28, 2010 7:17 PM EDT

BROOKLYN, NY - A pregnant woman probably looked like an easy target for a crook, but one robber learned the hard way when she gave chase.

The expecting mom had just dropped her son at school when a man ran up behind her, snatched her phone and took off running. She didn't let her baby belly get in the way - she chased him down, along with a group of witnesses.

The 18-year-old was cornered in a park, where he was arrested.