Tel Aviv, Jan 3 : Mossad Chief David Barnea on Wednesday said that people who are responsible for the October 7 attack have 'signed their own death warrant'. 'Let every Arab mother know that if her son took part in the October 7 massacre, he has signed his own death warrant,' Mossad Chief said. His quote seems to be loosely-inspired by Israel's first prime minister David Ben Gurion, who in a 1963 speech had said: 'Let every Hebrew mother know she has entrusted the fate of her (soldier) son to commanders worthy of it.' Mossad Chief was attending the funeral services of former Mossad chief, Zvi Zamir, who died on Tuesday. On Tuesday, Israel assassinated Hamas Deputy Chief Saleh al-Arouri in Beirut. Source said that Qatar -- which is one of the major negotiators between Israel and Hamas -- has asked the Israelis not to assassinate the Hamas leaders in Qatar. Hamas Political Head Ismael Haneyeh along with other top leaders including Khaled Mashel are living in Qatar. /IANS