An Australian journalist and photographer onboard aid boats headed for the Gaza Strip have not been heard from since at least 10 people were reportedly killed during a clash with Israeli commandos.
Israel's defence force says at least 10 people were killed when commandos stormed a convoy of six ships carrying aid to Gaza.
Commandos boarded the ships in international waters overnight, backed up by warships and helicopters.
He says the pair are on assignment covering the flotilla and have been moving from boat to boat - but were last known to be on the MV Samoud.
Both have satellite phones but Mr McGeough reported his GPS was not working, blaming the malfunction on Israeli attempts to jam communications.