WATERLOO - Patrol officers are keeping an extra eye on area businesses to deter or capture robbers who have been hitting stores on a regular basis.

"We're trying to be in the right place at the right time," said Capt. John Beckman with the Waterloo Police Department.

Officers have been doing business checks and paying more attention to potential targets. Beckman said employees also need to be vigilant, pay attention to who is entering stores and follow instincts when assessing suspicious people.

Since the beginning of the month, robberies have been reported every week. Thursday night saw the sixth and seventh holdups in Waterloo since Nov. 1.

In one, a worker at the Hy-Vee on Byron Avenue was hit by a gunman's forearm. The robber was demanding cash from the customer service counter about 6:15 p.m. in the back of the store.

The attack was unprovoked, Beckman said.

"She did what he wanted her to, and he still struck her," he said.

The employee was not hospitalized for her injuries.

About three hours later, two masked men accosted a driver for Red Apple restaurant who was delivering food to 139 Lehman Circle. The robbers assaulted the worker and fled with Chinese food, according to the police report.

The man who lived at the address said he did not order the delivery.

Authorities cannot say what caused the recent spike in robberies, but winter heists offer some advantages.

"This time of year provides the opportunity to do this sort of thing," Beckman said, noting it gets dark earlier, which provides cover.

Also, store employees pay less attention to people bundled up with their heads partially covered.

But Beckman warns they could be warding off cold or trying to conceal their identity.

Investigators don't know how many of the crimes are connected. Based on a description Thursday at Hy-Vee - a heavyset person 5 feet 6 inches tall weighing 200 pounds - the robber is likely not the same individual who pulled off some of the earlier jobs, Beckman said.

Contact Jeff Reinitz at (319) 291-1578 or jeff.reinitz@wcfcourier.com.