Two men have been shot in the middle of Parramatta in western Sydney, leaving one fighting for life

The pair are believed to have been in a car with two others when they were shot about 5.10pm today by somebody driving past.

One man, who was shot in the head, was rushed to hospital in a critical condition while the other was stable.

Authorities have set up crime scenes at the site of the shooting near Church Street and the Great Western Highway intersection, as well as at the location where a car was torched in a neighboring suburb.

The two uninjured men in the car were seen being questioned by police.

Church Street at Granville was closed in both directions this evening.

A Mercedes was destroyed by fire three and a half kilometres away at an apartment block Sherwood Street in Merrylands West.

A nearby tree also caught fire.

Police are investigating if the two incidents are linked.