The last five Turkish activists wounded during a bloody Israeli raid on an aid flotilla to Gaza earlier this week returned to Turkey late on Friday, hospital officials said.

The activists, who had been kept in Israel because their medical condition was too serious for them to travel sooner, were brought to Ankara by Israeli air ambulances and remain in intensive care, Metin Dogan, the chief physician at Ataturk Hospital said on Friday.

Of the 24 people being treated in Ankara, one is an Irish national, while the rest are Turkish, Dogan said.

"Seven of the patients are in critical condition, but their situation has improved since they returned," he said.

A prosecutor took statements from those in hospital who were well enough to speak, broadcaster CNN Turk said on its website. Turkish officials are considering legal action against Israel.

Kenneth Nichols O'Keefe, a former U.S. marine turned peace activist who was on board the Mavi Marmara, arrived at Istanbul's Ataturk Airport late on Friday, his face covered in streaks of dried blood.

O'Keefe is a veteran of the 1991 Persian Gulf War. In 2003, he organised a "human shield" mission to Iraq to try and prevent another U.S. invasion there. He told reporters at the airport that Israeli authorities beat him while he was in detention. He said, they treated us like dogs there.

"This is nothing compared to what others have gotten," he said. "I saw the mass murder that Israel perpetrated on the Mavi Marmara."

On May 31, an Israeli raid on the convoy of ships with more than 600 people on board killed 9 people and injured nearly 30 others. Eight of the nine killed were Turkish citizens, and the other was U.S. citizen of Turkish descent.

Agencies