Three girls, aged 16, 17 and 18, and a young man, aged 18, were arrested yesterday evening following a police chase on the M61.
The teenagers, all from Manchester, were the subject of a manhunt after a man in his 40s was killed in a collision in Freckleton Street, Kirkham at around 4.15pm.
Police said the car involved in the fatal collision is believed to have driven off from the scene.
Shortly after the incident police stopped a Nissan Micra in a road block between junctions 6 and 5 of the M61.
The four teenagers have been arrested on suspicion of murder and are in custody.
"While we have made a number of arrests our enquiries are very much on-going and I would appeal to anyone who witnessed these events or who has any information which could assist our investigation to come forward and speak to us."
Anyone with information should call police on 101 quoting log number 1068 of July 18 or independent charity Crimestoppers on 0800 555 111.