Direct from Fleetmon.com:

Offshore tug supply vessel MAERSK BATTLER at 0155 CET Dec 22 reported to MRCC Etel, France, sinking of one of two towed vessels, MAERSK SEARCHER , in position 48 05N 006 24W, some 80 nm west of Brest, Celtic Sea. Another vessel under tow, MAERSK SHIPPER , capsized, but remained afloat, permitting further towage, but MAERSK SHIPPER also sank at 0633 CET in position 48 01N 006 37W, some 87 nm west of Brest. Both vessels under tow were offshore supply tugs, understood to be decommissioned, to be towed to Turkey for dismantling. Both were unmanned, free of fuel, oils and other pollutants, i.e. their sinking doesn’t carry any environmental risks.

by Mikhail Voytenko