Live updates: Lebanese capital rocked by huge explosion

From CNN's Jennifer HanslerThe US Embassy in Beirut is urging those in the area of the explosion to “stay indoors and wear masks if available” due to reports of toxic gases released from the blast.An embassy security alert went out following the explosion."There are reports of toxic gases released in the explosion so all in the area should stay indoors and wear masks if available," the embassy warned.The embassy also urged US citizens in the affected areas to "contact their loved ones directly and/or update their status on social media."From Amir Tal and Andrew Carey in JerusalemIsrael is offering humanitarian medical assistance to Lebanon following the massive blast in Beirut Tuesday afternoon, even though the two countries have no diplomatic relations.“Under the direction of Minister of Defense, Benny Gantz, and Minister of Foreign Affairs, Gabi Ashkenazi, Israel approached Lebanon through international defense and diplomatic channels to offer the Lebanese government medical humanitarian aid,” a statement read.Following the announcement, Israel’s President Reuven Rivlin tweeted, “We share the pain of the Lebanese people and sincerely reach out to offer our aid at this difficult time.”Lebanon is one of a small number of countries Israel regards as an enemy state, and there have been no diplomatic relations since a ceasefire signed between the two countries in 1949.As recently as last week, Prime Minister Benjamin Netanyahu was warning that Lebanon, along with Hezbollah, bore “full responsibility” for what the Israeli army described as an infiltration by a Hezbollah cell into Israeli territory.From CNN's Jomana Karadsheh in Istanbul and Mia Alberti in LisbonThe aid agency Save the Children warned of children unaccounted for after a deadly explosion in Beirut that "wiped out entire streets," according to a statement from the organization."We are shocked and devastated by the explosion today.