Josep Lago/Getty Images(BARCELONA, Spain) -- Following a deadly vehicle-ramming attack in Barcelona Thursday afternoon -- which left at least 13 people killed -- a police operation was carried out 90 minutes south of the city in Cambrilla, during which five "terrorists" were killed, officials said.
Police said the operation was in response to a "possible terrorist attack."
Five "terrorists" were killed in the operation, but officials initially said four people were injured and one person was wounded and detained.
On Twitter, police said they "have killed the alleged perpetrators." Catalan police told ABC News that they believe the incident in Cambrils is related to the attack in Barcelona earlier on Thursday.
Authorities confirmed early Friday morning that the explosive belts carried by the alleged terrorists were fake.
"We work on the hypothesis that the terrorists killed in Cambrils would be related to the events in Barcelona and Alcanar," police said. Alcanar is the location of the earlier deadly house explosion that police said was believed to be connected to the Barcelona plot.
Also, Catalunya’s Emergency Services confirmed that in addition to the terrorists, five people were injured. One person is in critical condition, two are in serious condition, and two more are in mild condition.
At least 13 people died and more than 100 were injured when the van slammed into pedestrians in Barcelona's Las Ramblas district.
The U.S. State Department said one American was injured in the attack, although it did not identify the individual. "We can confirm one U.S. citizen suffered minor injuries," a State Department official said. "We are monitoring the situation closely and stand ready to provide consular assistance to any affected U.S. citizens."
And men's college basketball teams from Oregon State, Clemson, Tulane, Arizona and Grand Canyon were in Barcelona at the time of the car attack, but all teams took to Twitter and said everyone was safe and accounted for.
Australian Foreign Minister Julie Bishop said at a press conference Friday that four Australians were injured and one is unaccounted for. Greece's Ministry of Foreign Affairs said on its website that one Greek national was injured. And Belgium's Deputy Prime Minister and Foreign Affairs Minister Didier Reynders tweeted that one of its nationals was killed in the attack.
From team hotel in Barcelona, Oregon St. basketball coach posts somber video conveying the gravity of what took place outside his window. pic.twitter.com/s2zRktUnkk— ABC News (@ABC) August 17, 2017
Two individuals have been detained in relation to the van incident, police said. One person is a Spanish national from Melilla, and the other is from Morocco.
Neither of those detained was the driver of the van, police said. Police confirmed early Friday that they were still looking for the driver.
A third person was detained early Friday in Ripoll, approximately 66 miles from Barcelona. The suspect was detain in connection with the attacks, according to the department of the Interior.
ISIS has claimed responsibility for the Las Ramblas attack via its Amaq agency, according to the SITE Intelligence Group.
Catalonia's emergency services advised the community to "stay home" and "avoid going out."
Police have connected the incident to a house explosion in Alcanar, Spain, on Wednesday night. The explosion, which caused part of the building to collapse, killed one person and injured others, police said.
The two people who were arrested were detained in the same town as the house explosion, authorities said.
Police described a separate incident in which a car trying to get past a Barcelona checkpoint hit an officer and another person, police said. The incident killed one person and broke the officer's leg, police said.
Authorities said a man inside the car was shot by police, but they did not confirm whether the incident was connected to the attack in Las Ramblas.
A spokesperson for the Guardia Civil, Spain’s national police force, told ABC News the man who rented the van has been identified as Driss Oukabir. Police confirmed that Oukabir is one of the detained individuals.
An eyewitness told a Spanish television station that the driver of the van ran people over for nearly 1,000 feet before fleeing into a nearby Turkish restaurant.
The witness said the suspect had something in his hand, but he could not tell what it was.
Police said there is no proof that the man who left the car was armed but described the incident as a terror attack that attempted to kill as many people as possible.
Some of the injured went to the hospital on their own, said Catalonia's interior minister, Joaquim Forn, in a press conference Thursday night. The number of dead and injured victims could go up, Forn said.
Authorities are in the process of identifying the deceased, he said.
Spanish Prime Minister Mariano Rajoy expressed solidarity with the victims and their families, describing the attack as "jihadist terrorism."
Those responsible for the attack will be brought to justice, Rajoy said, stressing that the response to terrorism needs to be global.
Barcelona residents are suffering "the same pain and the same uncertainty" as their neighbors in Madrid, Paris, Nice, Brussels and London, Rajoy said.
Forn declared three days of mourning, and a moment of silence will be held on Friday at noon local time at the Plaza de Catalunya, Forn said. The king of Spain, Felipe VI, will be present for the moment of silence, the palace's official Twitter account announced.
El Rey estar? hoy en la plaza de Catalu?a de Barcelona para unirse al minuto de silencio en solidaridad con las v?ctimas del atentado.— Casa de S.M. el Rey (@CasaReal) August 17, 2017
Las Ramblas is a popular tourist area in Spain's second-largest city and was filled with people at the time of the attack, police said. Catalan police ordered an evacuation of the area.
Emergency services for the Catalonia region, of which Barcelona is the capital, posted tweets in multiple languages advising individuals to use social media to inform relatives of their whereabouts.
#Barcelona #Rambles If you are ok, please Inform your family using social networks to avoid the collapse of phone lines— 112 (@112) August 17, 2017
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