UPDATED with details of second attack: U.S. cable networks went live with coverage Thursday of what Barcelona police say was a “massive” act of terrorism in Spain’s second-largest city. Officials say at least 13 people were killed and more than 100 injured Wednesday after a van traveling at 80 km an hour (50 mph) jumped a curb and drove down the middle of a crowded pedestrian walkway in the Las Ramblas district, a popular tourist area. Officials today were still on the hunt for the driver of the vehicle.

Early this morning, Spanish officials confirmed that police thwarted a second attack in Cambrils, a seaside resort town about 60 miles south of Barcelona. In the early hours local time, troopers shot and killed five suspects, less than eight hours after the tragic afternoon in Barcelona, the capital of the country’s Catalonia region. Media reports say the Cambrils suspects got into a shootout with police after driving an Audi into a crowd of pedestrians on a boardwalk. Several injuries were reported and one woman was killed.

Spanish officials are now investigating a likely tie between the two terrorist acts as part of a wider plot. The probe has widened to include an explosion that occurred Wednesday night in Alcanar, a town southwest of Barcelona, which investigators now believe was a location the plotters were using to make a bomb, suggesting an even bigger attack was planned.

The number of dead in the Barcelona van attack is expected to rise as many suffered severe injuries, a police official said. ISIS has claimed responsibility, as it generally does with nearly every terrorist attack around the world. Spain’s Prime Minister Mariano Rajoy on Thursday night called the attack “jihad terrorism” and declared three days of mourning across the country.

The U.S. State Department confirmed that one American was dead and another injured in the attack but did not release more details. A Bay Area TV station interviewed a father who said his son was killed in the attack after being in Barcelona with his wife for their honeymoon.

Witnesses said the Barcelona van driver fled the scene on foot after plowing into the crowd. Spanish police confirm that they have arrested two men they believe were involved in the attack; neither was the driver of the van, but one of them had rented it. Local media has identified that man, but Deadline will not name him. Reports say the man posted anti-Israeli remarks on his Facebook page last night. Police say he rented the van used in the assault. There are no details yet about the second man in custody. There have been four arrests total in the investigation.

Local reports earlier said that two armed men were holed up a nearby bar, but police now confirm that is not the case and that there is no hostage situation.

Police cordoned off the scene of the attack, and officers — some in riot gear — were seen running down the streets and through a market, checking in stores and cafes.

The U.S. government is warning Americans to avoid the area.

Police on Thursday said a third separate incident, in which a car sped through a checkpoint outside Barcelona, injuring a police officer, was not related to the van attack. That driver was shot and killed after a chase about six miles from Las Ramblas.

Pundits on CNN, Fox News and MSNBC spent Thursday discussing jihadists, “lone wolves” and how the incident bears the hallmarks of ISIS-style vehicle-as-weapon attacks that have become all-too-familiar in Europe. In June, seven people died after a van drove into pedestrians on the London Bridge; a dozen people were killed in December after a hijacked trick plowed into a Christmas market in Berlin; and 84 people died and more than were 450 injured in July 2016 when a tractor trailer accelerated into a crowd gathered for Bastille Day fireworks in Nice, on the French Riviera.

Thursday’s attacks came just days after a white supremacist drove his car into a crowd of counterprotesters during the “Unite the Right” rally in Charlottesville, VA.

Lisa de Moraes and Patrick Hipes contributed to this report.