STOCKHOLM — Swedish crime writer Henning Mankell, author of the Wallander detective series, is one of nine Swedes held in Israel Monday after landing from a Gaza-bound aid flotilla attacked by Israeli commandos, Sweden's foreign ministry said.

Mankell "has been detained ... In all, nine Swedes have been detained," ministry spokesman Anders Joerle told AFP, adding that they were not all being held at the same place and some had been imprisoned while others had simply been taken into custody.

"I think Henning Mankell is just being held in custody. I'm not sure. The Israelis have him in some kind of detention," he said.

Some of the Swedes had been very slightly injured, Joerle said, adding that some Swedes believed to have been travelling with the flotilla when it was attacked early Monday had yet to be reached.

The nine Swedes have reportedly been given the choice between accepting to be deported or to be tried in an Israeli court.

Earlier Monday evening, the foreign ministry countered a rumour set in motion at an anti-Israel demonstration in Oslo that Mankell had been shot in the attack, which left at least nine pro-Palestinian activists dead.

The 62-year-old author of the Wallander detective series joined the flotilla from Cyprus by way of smaller boats "after almost 48 hours of playing hide-and-seek with Cypriot police," Ship to Gaza Sweden said in a statement.

Mankell, whose books about world-weary detective Kurt Wallander have sold more than 25 million copies worldwide and have been adapted to film and television, said he was taking part in the flotilla to show his solidarity towards the Palestinian people.

"I think that when one talks about solidarity, one must always know that actions are what proves destiny," he told Swedish public radio last Thursday.

"It is with actions that we prove we are ready to support something we believe is important," he said.

In addition to Mankell, Ship to Gaza Sweden said nine Swedes were in the flotilla when it was attacked, including controversial Swedish-Israeli artist Dror Feiler, a parliamentarian and several doctors and academics.

The ships, carrying more than 700 passengers, were on a mission to deliver some 10,000 tonnes of supplies to Gaza, which has been under a crippling Israeli blockade since 2007.

Israel had warned the attempt to break the blockade was illegal and that it would intercept the ships.