Israel-Gaza live updates: Police killed in border shooting, authorities say

Strikes targeted a Syrian scientific research area in the city of Masyaf in the Hama countryside on Sunday night, Syrian state media and the Syrian Observatory for Human Rights (SOHR) said.

"Ambulance vehicles rushed towards the center of the area" amid reports of casualties, the SOHR -- a U.K.-based war monitor -- said on its website.

Both Syrian state media and the SOHR attributed the strikes to Israel. The SOHR said Syrian anti-aircraft weapons intercepted some Israeli missiles.

There was no immediate confirmation on the number of casualties. At least five people were killed and 19 others were wounded, Syrian state news agency SANA reported. ABC News was not able to immediately confirm the reported casualties or whether they were military personnel.

ABC News asked the Israel Defense Forces for comment. Israel typically does not confirm or deny responsibility for strikes in Syria, where it has been engaged in a "shadow war" with Iran and its allies -- including the Lebanese Hezbollah militia -- for several years.

-ABC News' Ghazi Balkiz and David Brennan

The polio vaccination campaign continued today in south Gaza, Khan Younis and Rafah, after early issues in the region when vaccines could not be properly distributed to the eastern side of Gaza.

The Palestinian Ministry of Health announced Sunday that 441,647 children in Gaza have received the first dose of the polio vaccine, so far.

This accounts for about 69% of the targeted population, according to the ministry.

According to the World Health Organization, 95% of children need to be vaccinated to prevent the spread of the disease effectively.

On Monday, vaccinations will be offered in northern Gaza where daily, eight-hour pauses in fighting and airstrikes will be instituted so children can be taken to one of the roughly 33 locations across Gaza City and north Gaza where the vaccine will be administered, according to the ministry.

-ABC News' Victoria Beaulé

Israel closed on Sunday the two land crossings between Jordan and Israel, as well as the Allenby Bridge crossing between Jordan and the occupied West Bank, the Israel Airports Authority -- which oversees the crossings -- told ABC News.

The closures followed a shooting on Sunday morning at Allenby that killed three police officers.

The gunman -- who was shot dead by security forces -- came from the Jordanian side, but it was not immediately clear if he was affiliated with any militant group. Both Hamas and the Islamic Jihad issued congratulatory statements about the shooting.

Netanyahu condemned the attack, saying it was attributable to the "murderous ideology led by Iran's 'Axis of Evil'."

Israel did not say how long the closures would last. The Allenby crossing is one of the key entries through which goods destined for Gaza pass.

-ABC News' Jordana Miller, Nasser Atta, Victoria Beaule and David Brennan

The Israel Defense Forces (IDF) reported the killing of a Hamas rocket commander in an airstrike last week.

The IDF wrote on social media on Sunday that its Southern Command "eliminated" Raef Omar Salman Abu Shab -- the commander of the rocket unit of the eastern Khan Younis Brigade -- in an airstrike on Tuesday

The commander was "responsible for launching rocket barrages from the area of Khan Younis toward southern and central Israel since the start of the war," the IDF said.

-ABC News' David Brennan