DALLAS (CBSDFW.COM)– When Dallas officer Ronald Workman arrived at an apartment complex in the 3500 block of Timberglen Road in North Dallas on Monday, police say the 66-year-old drove right into an ambush.

Investigators say the gunman, 19-year-old Bryson Howard, called 911 to lure police into the complex, before shooting officer Workman in the jaw.

Just hours earlier, police chased a robbery suspect into a Pleasant Grove apartment complex. Officers say William Banks hid behind the laundry room and waited to ambush them. Banks was shot and killed.

“Our officers survived both these ambush situations that could have led to much dire circumstances,” said Dallas Police Chief, David Brown.

Many officers are wounded or killed in the heat of the moment; during bank robberies, chases, or while rescuing hostages. But according to Dallas Police Association President Ron Pinkston, plotting to kill an officer happens more than we think.

“It’s a trend that increased last year with unprovoked assualts on police,” explained Pinkston. “FBI stats show that the number two situation for police deaths is ambush,” he added.

In November, 2010, two Dallas police officers responded to a family violence call at a Pleasant Grove apartment. The gunman waited in a dark breezeway and opened fire with an assault rifle. One of the officers was hit several times, but survived.

UT-Arlington criminal justice professor Randall Butler sees the growing trend.

“Ambush is a problem within the profession of law enforcement. It’s something that has been recognized since the 1990s,” explained Butler.

Butler is also a reserve police officer and says ambushes are usually plotted by males in their 20s or 30s with pychological problems. The criminal justice professor also believes that family violence calls tend to lead to more ambushes compared to other police calls.