Israel has taken the unusual step of jailing a suspected Jewish militant without trial following the death of a Palestinian infant in an arson attack.
Mordechai Meyer, a resident of a Jewish settlement in the West Bank, has been placed under administrative detention for six months.
He is suspected of violent activity as part of a Jewish terror group.
Israel has used administrative detention orders against Palestinians but not against Jewish suspects.
The use of such orders against Jews suspected in Friday’s arson in the West Bank was among new measures approved on Tuesday by Prime Minister Prime Benjamin Netanyahu’s security cabinet.
The attack killed 18-month-old Ali Saad Dawabsha, a Palestinian toddler, and severely injured three relatives in the West Bank village of Duma.
The child’s parents and four-year-old brother were seriously injured in the attack, suspected to have been carried out by Jewish settlers.
Detention without trial is necessary, Israel says, to stop further violence in cases where there is not enough evidence to prosecute suspects, or where going to court would risk revealing the identity of secret informants.
Civil liberties groups have frequently criticised administrative detention orders as an abuse of due process of the law.
On Monday Israel said it could use harsh interrogation methods to tackle violent Jewish extremism, after the death of the Palestinian infant.
Interior Security Minister Gilad Erdan told Israel Radio that suspected Jewish extremists may be shaken violently in custody – a controversial treatment used on Palestinian suspects.
Mr Netanyahu earlier described the Duma attack as “an act of terrorism in every respect”. He said every effort was being made to capture those responsible.
However, the Palestine Liberation Organisation (PLO), which dominates the Palestinian Authority in the West Bank, said it held the Israeli government “fully responsible” for the death which was the result “of decades of impunity given by the Israeli government to settler terrorism”.
About 500,000 Jews live in more than 100 settlements built since Israel’s 1967 occupation of the West Bank and East Jerusalem. The settlements are considered illegal under international law, though Israel disputes this.