An Indiana sheriff’s deputy was shot three times Friday morning in a hospital emergency room by a stranded motorist he had stopped to help and later learned might be connected to an earlier crime, authorities said.

La Porte County Sheriff’s Deputy Jon Samuelson, a 12-year veteran of the force, was airlifted to South Bend Memorial Hospital and remains in critical condition.

The alleged gunman, Sharod Grafton Jr., was arrested in the woods near the hospital minutes after the shooting.

Samuelson, 33, was driving to a training session around 6:45 a.m. when he stopped to help a stranded motorist, Grafton, on State Road 2, authorities said.

At some point the deputy took Grafton, a Chicago resident, to Franciscan Hospital in Michigan City at his request, police said.

“Once at the hospital, the officer learned that the subject may have been involved in an earlier criminal incident,” Indiana State Police Sgt. Glen Fifield told reporters.

“The officer returned inside the hospital where an altercation took place in the emergency room between the suspect and himself, which resulted in the suspect producing a firearm and shooting the officer.”

Authorities did not specify the crime Grafton is allegedly connected to.

Grafton fled into a nearby wooded area but was quickly arrested, authorities said. A handgun believed to have been in his possession was found, police said.

“This is a senseless shooting that didn’t have to take place,” Fifield said.

“Our officers and deputies from the La Porte County Sheriff’s Department and all over the state of Indiana and Illinois risk their lives every day. This officer thought he was helping a stranded motorist and it turned into this. So once again, he was out helping somebody and it turned into this.”

Samuelson, who is married with no children, comes from a “long lineage of law enforcement,” police said.

His grandfather was the chief of police for the city of La Porte, and his father is a retired Michigan City police officer, authorities said.

The La Porte County Sheriff’s Office called the shooting an “isolated incident” and said there was no immediate threat to the public.

The Indiana State Police are leading the investigation into the shooting.

Charges are pending against Grafton, who is being held in the Porter County Jail.

“La Porte County friends and neighbors, we are asking for our community to rise up, rally together, and lift Deputy Jon Samuelson and his family in prayer and support during this incredibly challenging time,” La Porte County Sheriff Sheriff Ronald Heeg.

In a statement, Franciscan Health said the safety and health of its patients are always the top priority.

“The emergency department remains on ambulance bypass, but walk-in patients are being accepted through the main entrance to the hospital,” the hospital said.

“Franciscan Physician Network medical offices on site are closed at this time. All other services and departments remain open as normal.”