According to twitter user AviationGistNg, an helicopter belonging to Bristow has crashed somewhere in the Lagos Atlantic ocean.

There is no word yet on possible casualties. Search is ongoing and we will bring you updates as we get them

Bristow says what happened was a prepared ditching (which means that the pilot noticed a fault and decided to crash land).
Thank God it ended well. Recall that last year another Bristow helicopter crashed in the Lagos lagoon and lives were lost, but this one has a happy ending.