Catalan police were checking coaches, buses, and minibuses in Barcelona on Monday, after the local media reported on a possible terror plot involving a 30-year-old Moroccan. The man is reported to have a bus driver license. The daily El Periodico de Catalunya said that the police had circulated an internal note saying that the man could drive a bus into civilians.

Read more: Barcelona police shoot knife attacker

The authorities also boosted police presence at popular tourist landmarks, including the Sagrada Familia Cathedral and the Las Ramblas Boulevard, according to the Spanish daily El Pais. In 2017, a 22-year-old Moroccan drove a van into crowds at Las Ramblas, killing 16 and injuring 131 people. He was killed several days later.

On Sunday, the US State Department unexpectedly tweeted a terror warning to travelers in Barcelona. The message advises visitors to exercise "heightened caution" around vehicles "including buses" in the Las Ramblas area.

"Terrorists may attack with little or no warning, targeting tourist locations, transportation hubs, and other public areas," the US officials said.

Talking to Rac1 Radio on Monday, Catalonian Interior Minister Miquel Buch confirmed that the police were "working on this threat."

"All of [the threats] are being investigated," Buch said. "This is one more."

Read more: Bomb scares set off security alerts in Barcelona

Buch also defended the decision not to raise Spain's threat level, which the authorities have long held at four out of a maximum of five.

The official said it would be a "mistake to allow ourselves to live in fear."

"We need to be able to live in absolute freedom and normality," he told the radio station. "If we don't, we are handing them the victory."

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dj/aw (AFP, EFE)

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