London's ring road was closed Monday evening at 11:30 pm, after the discovery of the sinkholes of the central reserve located between Junction 4 (Orpington) and 5 (Sevenoaks).

The cause of the chasms is not clearly defined, but Highways England has confirmed that a "complete repair" was made to remedy the problem before the reopening of the road in the early hours of Tuesday morning.

The sinkholes were discovered as a result of an accident on a nearby highway portion.

M25 sink hole

M25 sink hole

"Two big holes in the sink appeared Monday in the Central Reserve on the M25 between junctions 4 (Orpington) and 5 (Sevenoaks)," confirmed a spokesman for Highways England.

"The sink holes did not affect the road surface of the M25 but our assessment showed that we had to close the M25 as a precaution during the repair.

"A complete repair is now complete and we have completely reopened the M25 at Tuesday morning rush hour."

Connect Plus Services (CPS) – consisting of Balfour Beatty, Atkins and Egis Road Operation UK – operates and maintains the M25 motorway network, including all major routes and ramps on behalf of Highways England.

Unlike the 11 other Highways England regions, the M25 is governed by a privately funded design, construction, financing and operation contract.

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