Israeli Prime Minister Naftali Bennett received a threatening letter Tuesday containing a bullet, local media reported.
The Israeli Public Broadcasting Corporation (KAN) reported that police have launched an investigation into the letter, which was sent to Bennett's home in the city of Ra'anana in central Israel.
Israel's Shin Bet internal security agency and the police are working to determine the source of the letter.
The Shin Bet has also stepped up security for Bennett's family.
"No matter how deep the political strife may be, it should not reach the level of violence, bullying and death threats," Bennett said in a post on Twitter.
"We need to do everything, as leaders and as citizens whose future and the future of their children is in this country, so that such phenomena simply do not exist.
"We are all people. Arguments and disagreements - yes. Bullying and threats - no," he said.
"Besides being a politician and Prime Minister, I am also a husband and a father. So I have to protect my wife and children as well," he noted.
He called on politicians, particularly those who actively use social media, for calm and reconciliation.
Israeli police had taken action against some citizens on the grounds that they had threatened Bennett before.
