[Ammi]

Youtube video

Police are hunting for a gunman after three people were shot during a dispute at an office complex in Phoenix, Arizona.

The victims were reportedly taken to hospital on Wednesday morning. One was said to be in "extremely critical" condition while two others were less seriously injured.

However, Fire Captain Scott McDonald said all the victims had life-threatening wounds.

Officer James Holmes said police believe there is only one suspect, but that witnesses gave conflicting information about how he left the scene.

The shooting did not appear to be a random act, said Sergeant Tommy Thompson.

Sgt Thompson said a dispute with someone at the building turned heated, and the suspect pulled out a gun and started shooting. He said he did not know what type of gun was used.

The central Phoenix building has been evacuated and police are still looking for a suspect and any additional victims.

Vanessa Brogan, who works in an insurance business in the three-story complex, said she heard a loud bang that she first thought was made by someone working in or near the building.

She said other people thought they heard multiple loud noises. She said people locked themselves in offices until police evacuated the office park

The complex houses insurance, medical and law offices.

Becky Neher, who also works in the building, said she heard two gunshots and saw two victims lying on the ground outside the back of the building.

"Someone yelled, 'We have a shooter,' " she said. Ms Neher said medical workers who have offices in the complex came out to help the victims