The M62 was shut in both directions overnight due to what has been described as a 'serious collision'.
The road was closed between Junction 7 at Rainhill and Junction 8 at Westbrook near Warrington.
National Highways North-West announced the closure on Twitter just after 3am on Wednesday.
Officers from North West Motorway Police were at the scene along with National Highways personnel.
The westbound lanes reopened at about 5.30am, while the eastbound carriageway remained closed.
National Highways: North-West said earlier: "Please be aware the #M62 is currently closed in both directions between J7 #Rainhill and J8 #Westbrook near #Warrington due to a police led incident. We are in attendance assisting @NWMPG.
"Please approach with caution. More info to follow."
National Highways provided the following diversion routes:
Eastbound
Road users are advised to follow the solid black triangle diversion symbol on road signs.
- Exit the M62 at J7 and join the A57 eastbound.
- At Lingley Green turn left (north) onto Lingley Green Avenue.
- Follow Lingley Green Avenue to the roundabout with Whittle Avenue.
- At the roundabout turn left and join Whittle Avenue.
- At the next roundabout continue north and join Burtonwood Road towards the M62.
- Re-join the M62 at J8.
Westbound
Road users are advised to follow the hollow black square diversion symbol on road signs.
- Exit the M62 at J8.
- At the junction take the second exit and join Burtonwood Road south.
- At the next roundabout continue south and join Whittle Avenue.
- At the next roundabout turn right (west) and join Lingley Green Avenue.
- Follow Lingley Green Avenue to its junction with the A57.
- At the junction turn right (west) to join the A57 west.
- Follow the A57 to re-join the M62 at J7.
In an update published shortly after 5am, traffic information service Inrix confirmed the westbound carriageway has reopened. The eastbound route remains closed.
Highways England said on Twitter: "The westbound carriageway has reopened and traffic is flowing freely. The eastbound carriageway remains closed and is likely to be protracted. Please be aware if travelling on the #M62 eastbound from #Liverpool and surrounding areas this morning."
