Portland police are investigating an unusual spate of car break-ins that happened Monday night and early Tuesday morning in the area between the West Bayside and Parkside neighborhoods.

Police said the cars were parked in the area of Somerset, lower Preble and State streets and in each instance windows were smashed to gain entry.

The spree is unusual because, historically, most car burglaries in the city have targeted unlocked cars. The number also is unusual. It’s twice the number reported to the department most weeks, said Acting Chief Vern Malloch.

Thieves took cash and in many cases left other valuables behind, including credit cards and electronics. Blood was left on some of the cars, suggesting the thief or thieves injured themselves. Police have taken samples of that blood to be sent to the Maine State Police crime lab in Augusta to develop a DNA profile, Malloch said.

That profile can then be matched against profiles that exist in the state’s database to seek a match. A match could help police solve the crime and, even if it doesn’t, that profile will be stored in the database inc case there is a match in the future.

That process takes time and because it is a property crime, not a violent one, it will get a low priority at the lab, he said. Police can process fingerprints at the department and upload those into local and national databases in search of a match.

Police ask anyone who saw anything suspicious in that area or anyone who has information about the crimes to call 207-874-8533 if they witnessed any suspicious activity in those neighborhoods.

To provide information anonymously:

• Mobile phone users can text the keyword “GOTCHA” plus their message to 274637 (CRIMES).

• Go to the Portland Police Department website: www.portland-police.com and clicking “Submit an Anonymous Crime Tip.”

• Call the department’s Crime Tip line at: 874-8584.