(COLORADO) — The state of Colorado was rocked Monday by a mass shooting at a grocery store in Boulder.  Police tell ABC News the “active shooter” was reported at a King Soopers grocery store.

Police tell ABC News that authorities were responding to reports of a person shot in the parking lot.  When officers arrive, the gunman opened fire.

Sources claim the gunman used a long gun. 10 people, including a Boulder police officer, have been confirmed dead, but the number of persons injured remains unknown.  That number can chance, says Boulder District Attorney Michael Michael Dougherty, who says authorities are still notifying next of kin.

The slain officer was later identified as 51-year-old Eric Talley, who joined the force in 2010.

Talley’s father, Homer Talley, spoke about his son in a statement to ABC News.

“He took his job as a police officer very seriously. He had seven children. The youngest is 7 years old. He loved his kids and his family more than anything,” he said, adding Eric was training to be a drone operator to remove himself from the front lines because “He didn’t want to put his family through something like this.”

The state SWAT team responded to the shooting, as well as several law enforcement agencies.  The FBI also arrived to investigate.

According to video taken by witnesses, the gunman was apprehended alive and walked out of the store with his hands up to surrender.  Boulder Police say the suspect, who has not been identified, was injured and was taken to a hospital.

Currently, the motive is unknown, but police say there are no additional suspects at this time.

Colorado Governor Jared Polis tweeted out a statement Monday, writing, “My prayers are with our fellow Coloradans in this time of sadness and grief as we learn more about the extent of the tragedy.”

A King Sooper spokesperson said in a statement, “Our hearts are broken of senseless act of violence.”

The story is developing.