Police allege the suspect had stolen the vehicle in the central Drassanes area near Barcelona's old port, while the driver was making deliveries of butane gas.
Mireia Ruiz, a woman who saw the truck from her home nearby, said the driver ignored people screaming at him to stop as he sped down the wrong side of a ring road.
It has been reported officers shot at the vehicle to stop it on a road near the city's harbour this morning.
Spain's Interior Minister, Juan Ignacio Zoido, tweeted images of the stopped lorry, which displayed a bullet hole through the windscreen and a cage load of loose barrels.
It was not immediately clear if anyone was hurt by the speeding vehicle.
Officers reportedly opened fire as the man was driving the lorry the wrong way along the Roda del Litoral motorway towards the heart of the city.
La Vanguardia newspaper has reported that the man arrested was a Swedish citizen who may have been under the influence of drugs.
Berggren, born in 1984, was uninjured.
Three former U.S. gymnasts detail sexual abuse from team doctor
But the therapist is expected to wear surgical gloves in all circumstances and have a chaperone present if the patient is a minor. The FBI also has Go Pro video of Nassar allegedly molesting girls in a pool. (Michigan Attorney General's office via AP, File).
Jordi Sintes, a researcher at the IMIM, witnessed the truck being taken from outside his workplace, in Dr Aiguader Street.
"We have all turned and seen the butane truck braking suddenly at the entrance to the Round". Two motorbikes from the police force followed it. They have got off and pointed the driver with their pistols.
'In a matter of minutes, cops appeared from all directions - some with machine guns.
Spanish police are always awaiting the results to determine whether he consumed drugs as well as alcohol before his insane drive through Barcelona.
'In less than five minutes they had him handcuffed'.
Officials say due to his erratic behaviour they believe he was on drugs.
Some 84 were massacred before Bouhlel was stopped by police.