JERUSALEM, Feb. 14 (UPI) -- Israeli authorities warned installations at home and abroad to be on the alert after the assassination of senior Hezbollah terrorist Imad Mugniyah in Syria.

Mugniyah was killed in Damascus in a Tuesday car bombing the Lebanese Shiite terror group said was carried out by agents of Israel's Mossad intelligence service.

Lt. Gen. Gabi Ashkenazi, the military chief of staff, ordered the alert level to be raised on the ground and in the air in order to protect Israel's northern border.

Israeli Defense Minister Ehud Barak sent homeland defense units to reinforce troops on Israel's northern border Thursday, Haaretz said.

Security officials said the army was prepared for any attempt by Hezbollah terrorists to infiltrate Israel including by sea or air. Israeli embassies and consulates worldwide have been warned as have other representative bodies, such as El Al Airlines and Jewish Agency branches overseas.

Israel has denied it was responsible for Mugniyah's death.

"Israel has been under threat since the day it was established, and we know how to handle these threats and will do so now as well," said Israeli Foreign Minister Tzipi Livni in Washington.