A seven-year-old boy was hit by a seemingly stray bullet Thursday night during the targeted shooting of a man at a townhouse in Oshawa, Ont., Durham regional police say.

Police say the 23-year-old man was shot just after 10:30 p.m. Thursday at the home on Colborne Street West while standing in the doorway or just outside the front door. The boy was shot in the buttocks.

The boy's 15-year-old sister told CBC News the man opened fire outside the house right in front of her. Then she heard her mother call out, "Your brother just got shot."

"All I could do was scream," the girl said when asked by reporters about her reaction to seeing her little brother wounded and bleeding on the floor.

"No tears … I was in such shock. I'm running, telling everyone, 'Call 911.' No one would call 911. We had no phone," said the teen, who cannot be identified under the Youth Criminal Justice Act.

She also told reporters she saw the assailant open fire as she stood outside the home just a few metres from her front door, identifying him as "a black male."

"I saw the whole thing.… He had a hood over his face and he just bent down and fired three shots," she said.

She said the gunman ran right by her but said nothing as he fled.

"We're going to stay in a different place for a while, because we don't feel comfortable here now."

'Don't cry. I'm fine,' says boy

As for her little brother's condition, she told reporters, "He's doing well.… He's taking it like a champ. Every time we cry, he's like, 'Why are you crying? Don't cry. I'm fine.'"

One neighbourhood resident, who does not want to be named, said she saw a man approach the townhouse from a nearby parking lot and initially thought he was a friend of the family, although she didn't understand why he looked mad.

"He didn't even get in the house, just bang bang bang," said the woman. "Then I saw puffs of smoke and then I heard them screaming."

The woman said the gunman started walking away quickly toward her and some others standing on the sidewalk, so she jumped out of the way. The man then started to run and went around the corner, where she believes he got into a grey or silver four-door car with tinted windows. She said she saw the car speeding away.

Another person, Tanya West, a next-door neighbour who was awoken by the gunshots and then ran downstairs to check things out, said: "It was pretty traumatic."

The boy is believed to have been wounded by a stray bullet in a shooting that targeted a man at the house. (Linda Ward/CBC)

"I looked in the door, and [the boy's] mum and him were standing there and he was bleeding all over," said West. "They just told me that someone came in and started shooting. They don't know who he was."

Investigators said the man who was shot is known to police and attended a local hospital before paramedics arrived on the scene. His injuries are serious, but non-life-threatening, according to police.

Durham police's canine unit was called to the scene to try to track down the gunman. (Tony Smyth/CBC) Paramedics took the boy to hospital with minor injuries.

Investigators called in the police canine unit, but did not find a suspect.

Police are describing the suspect as a black man who was wearing a grey sweatshirt and black jeans at the time of the shooting.

Investigators said everyone inside the townhouse has been co-operating with police. On Friday morning, officers will canvass the neighbourhood, interviewing witnesses and looking for security video.

"You never expect a little boy is going to be shot right beside you," said West, who added that to her knowledge, there haven't been any shootings in the area since she moved into the townhouse complex eight years ago.

"It could have been really bad, and it's kind of scary, actually, to know that someone is just going to walk in and start shooting."