On Friday, Somerville police arrested two nonresidents after observing an alleged crack cocaine deal transpire at a residential complex that the Drug Control Unit has had under surveillance.

The apartment complex at 22 Kent St. near Union Square has been under police surveillance as part of an ongoing cocaine investigation. While there on Friday afternoon Feb. 18, detectives allegedly observed a Cambridge woman exit the building, pace in front of her car while speaking on her cell phone and then sit in her car in the parking lot. The woman was later identified at Shatika Conward, 24, of 86 Howard St., Cambridge.

According to police, a second vehicle then arrived and Conward entered the second car. Officers allege that they observed the exchange of an object before Conward exited the car about one minute later.

“Based on our collective training and experience and the information provided to us through other sources, we believed that these actions were consistent with a street level narcotics transaction,” states the police report.

Both cars then left the parking lot and were pursued by police. Jeffrey Zajac, 40 of 74 Main St., Woburn, was stopped first and a clear plastic bag believed to contain crack cocaine was allegedly found in his vehicle. Conward was stopped next. Police also allegedly recovered a similar baggie containing what appeared to be crack cocaine from her coat pocket.

Conward was arrested at 622 Somerville Ave. (in front of the Family Dollar Store) and charged with drug possession to distribute, distribution of a class B drug, and conspiracy to violate drug law. Because the alleged transaction took place within 1,000 feet of Conway Park, Conward was also charged with a drug violation near a school or a park, which carries a mandatory two-year sentence if convicted.

Jeffrey Zajac was arrested and charged with possession of a class B drug and conspiracy to violate drug law. He was also booked for two warrant charges for motor vehicle violations.