Israeli police have detained a Jewish left-wing activist with links to a man arrested earlier this month on suspicion of informing on Palestinians who sold property to settlers, the Israeli media reported Tuesday.

The reports said only that a second activist connected to the first detainee had been arrested, and gave no further details.

There was no immediate confirmation from the police.

Selling land to Israelis is viewed as treason by the Palestinians, and carries a penalty of life imprisonment. In several cases alleged vendors have been killed by vigilantes.

On January 11, police arrested a Jewish Israeli described as a “far-left activist,” as he sought to depart from Ben Gurion International Airport, without naming him.

Media reports said he was suspected of informing on Palestinians selling property to settlers, after being caught on hidden camera taking pride in handing details of vendors to the Palestinian security forces.