Russia's southern region of Dagestan held the first of three days of mourning Monday following a rampage by Islamic militants who killed 19 people, most of them police, and attacked houses of worship in apparently coordinated assaults in two cities.

Sunday's violence was the latest that officials blamed on Islamic extremists in the predominantly Muslim region in the North Caucasus, as well as the deadliest in Russia since March, when gunmen opened fire at a concert in suburban Moscow, killing 145 people.

The top U.S. military officer has warned that any Israeli military offensive into Lebanon would risk an Iranian response in defense of the powerful Hezbollah militant group there, triggering a broader war that could put U.S. forces in the region in danger.

Air Force Gen. CQ Brown, chairman of the Joint Chiefs of Staff, said Sunday Iran "would be more inclined to support Hezbollah." He added that Tehran supports Hamas militants in Gaza, but would give greater backing to Hezbollah "particularly if they felt that Hezbollah was being significantly threatened."

Israeli Prime Minister Benjamin Netanyahu has said that the current phase of fighting against Hamas in Gaza is winding down, setting the stage for Israel to send more troops to its northern border to confront the Lebanese Hezbollah.

The comments Sunday threatened to further heighten the tensions between Israel and Hezbollah at a time when they appear to be moving closer to war. Netanyahu also signaled that there is no end in sight for the grinding war in Gaza.

Thousands of fighters from Iran-backed groups in the Middle East are ready to come to Lebanon to join with Hezbollah in its battle with Israel if the simmering conflict escalates into a full-blown war, officials with Iran-backed factions and analysts say.

Almost daily exchanges of fire have occurred along Lebanon's frontier with northern Israel since fighters from the Hamas-controlled Gaza Strip staged a bloody assault on southern Israel in early October that set off a war in Gaza.

U.N. Secretary-General Antonio Guterres has warned that fighting between Israel and Hezbollah must not turn Lebanon into "another Gaza."

Guterres cited increased "bellicose rhetoric" from both sides as they engage in nearly daily exchanges of fire across the Israel-Lebanon border in parallel with the war in the Gaza Strip, and he said they risk triggering a catastrophe "beyond imagination."

A commercial ship traveling through the Gulf of Aden saw explosions near the vessel, authorities said Saturday, likely the latest attack by Yemen's Houthi rebels attempting to target the shipping lane.

The apparent fire by the Houthis comes after the sinking this week of the ship Tutor, which marked what appears to be a new escalation by the Iranian-backed Houthis in their campaign of attacks on ships in the vital maritime corridor over the Israel-Hamas war in the Gaza Strip.

Qatar’s foreign minister has said that some progress has been made in negotiations over a Gaza cease-fire deal but gaps remain between Israel and Hamas.

Sheikh Mohammed bin Abdulrahman Al Thani, whose country is a mediator alongside the U.S. and Egypt, said “there has been progress to some extent in the situation.”

Israeli forces have shelled tent camps for displaced Palestinians outside Gaza's southern city of Rafah, killing at least 25 people and wounding another 50, according to the territory's health officials and emergency workers.

This was the latest deadly attack in the Gaza Strip, where hundreds of thousands have fled fighting between Israel and Hamas. It comes less than a month after an Israeli bombing triggered a deadly fire that tore through a camp for displaced Palestinians in southern Gaza, drawing widespread international outrage — including from some of Israel's closest allies — over the military's expanding offensive into Rafah.

Taylor Swift fans enjoy parsing the singer-songwriter's lyrics for references to her romantic life and insights into her state of her mind.

But the pop superstar's fans in the U.K. didn't have to listen closely to her latest album, "The Tortured Poets Department," to get the sense that Swift had soured on the country's capital city after long making it a regular hangout and then her second home. The record's fifth track is titled "So Long, London."

Try saying "no" when a child asks for a smartphone. What comes after, parents everywhere can attest, begins with some variation of: "Everyone has one. Why can't I?"

But what if no preteen in sight has one — and what if having a smartphone was weird? That's the endgame of an increasing number of parents across Europe who are concerned by evidence that smartphone use among young kids jeopardizes their safety and mental health — and share the conviction that there's strength in numbers.