Victoria, B.C., activist Kevin Neish, who was arrested aboard a Gaza-bound aid flotilla earlier this week, says he was brutalized while detained in Israel.

At least nine people were killed and dozens more wounded after Israeli commandos raided six ships carrying 10,000 tons of aid and some 700 activists early Monday morning.

The ships were ordered to stop their journey into Gaza, which has been under an Israeli blockade for three years. They were then boarded about 130 kilometres from the coast in international waters and their occupants arrested – including three Canadian citizens.

Neish, 53, stepped back onto Canadian soil on Saturday at Toronto Pearson International Airport with a heavy heart.

"I'm sad, because I left some people behind that were in Israeli jails," he said.

Neish was detained in Israel for three days. He said his Israeli captors repeatedly threatened him with death, but added that others experienced far worse.

"There was a fellow that was locked up that didn't get out with me and he turned up this morning in Istanbul, a split down the middle of his head and blood from head to toe."

Although official numbers from Monday's violent confrontation pegged the number of fatalities at nine, Neish said he had a different count.

"Sixteen people were murdered on the boat, my boat."

He also repeated claims that the Israeli soldiers had fired upon the flotilla from helicopters before the raid began, which contradicts Israel's account that the commandos acted in self defence.

He admitted that some on the ship were armed with chains, pipes and sticks.

Neish is scheduled to arrive at the Victoria airport between 8 p.m. and midnight, and will make a short statement about his ordeal.

Friends and family of Neish describe the marine engineer as a "role model" who had travelled on many international humanitarian missions in the past. He was tasked with protecting a team of news reporters travelling with the flotilla.

Canadian citizens Rifat Audeh of St. Catharine's, Ont., and Farooq Burney were also arrested on the flotilla but have since returned to family in the middle east.

Mark Regev, a spokesperson for Israeli Prime Minister Benjamin Netanyahu, said the flotilla had been warned in advance that the ships would not be allowed to enter Gaza from the sea.

Israel has let five aid deliveries go through the blockade on previous occasions, but has blocked all such attempts since January of last year.

Mass protests across Canada

The raid sparked considerable outrage from groups across Canada, which organized demonstrations from Halifax to Vancouver over the weekend.

In Ottawa, protesters rallied to denounce the blockade against Gaza and to demand the federal government advocate for human rights in the Palestinian territories.

Prime Minister Stephen Harper issued a statement following the raid. It said that Canada "regrets" the deaths and that Ottawa was seeking more details "to shed light on what exactly happened."

The Egyptian and Israeli navies have blocked almost all supplies to Gaza since Hamas was voted into power in 2007. Hamas, an Islamic militant group, is considered a terrorist group by several Western countries, including Canada and the U.S.

With files from The Canadian Press