Police say a gunman stormed an office tower in North Dallas, shooting a father and a son, MyFoxDFW.com reports.

Authorities say the gunman shot a 63-year-old man in the legs and his 39-year-old son in the neck at a business they own on the third floor.

Dallas Police Lt. Andrew Harvey said the gunman pointed his gun at arriving police, who fired at him and missed. The suspect then shot himself, police said.

"This is not a random offense. They were targeted. The suspect knew both of the victims," Harvey told MyFoxDFW.com.

Harvey said gunman is now in "very critical" condition at an area hospital and the victims are both in stable condition, MyFoxDFW.com reports.

During the shootings, the building was on lockdown and about 16 people took refuge in the vaults in the bank on the building's first floor.

A witness tells KRLD-AM of Dallas that a bank customer went outside, then came back inside and said, "You'd better lock your doors." Another witness reported seeing a man sitting in a chair with blood all over his chest.

Police did not immediately release more information including the identities of the alleged gunman and the father and son.

Click here for more on this report from MyFoxDFW.com

The Associated Press contributed to this report.