Several people were detained by Swedish police on Saturday in connection with the bomb threat in the western Swedish city, all but two have now been released but all remain interesting to the investigation.

The alleged offences involving both those arrested and those released have been classified as conspiring to commit terrorist attacks. Aside from that the police remain restrictive with details concerning the case.

“We know that this is diffuse and mysterious. But it could be that you are going to have an ‘aha reaction’ in hindsight and understand why we choose to work in this way,” said police spokesperson Björn Blixter.

Blixter concluded that the police were satisfied with their work.

“There remains no one on the loose,” he said, adding that interviews have been conducted with the suspects during the course of the day.

According to broadcaster TV4 three people, all men, were detained in the Angered district of the Gothenburg, but the police have not confirmed the number of suspects involved in the case.

Despite the arrests the threat remains, police have confirmed, but declined to elaborate on whether there were further possible suspects.

“The threat against central Gothenburg has not been warded off with today’s arrests. We stand by what we said initially, which is that a bomb is to be detonated somewhere in central Gothenburg on Saturday,” said Björn Blixter.

Police revealed Friday that they had been tipped off “by a credible source” that a bomb attack was planned in central Gothenburg.

There is currently no indication that the raised threat level will continue throughout Sunday, but the police will retain their higher profile in central Gothenburg during the day.

“We don’t know if we have all the people involved and what else could happen, therefore we want to retain our pledge to retain a broad presence in the city centre,” Blixter said.

A decision will be taken over the threat level on Sunday, he said.

According to TV4 national police units have been called in to Gothenburg.

Despite the bomb threat, retailers have been operating as normal for a Saturday and the city centre has been thronging with people.

“Those behind this are not going to stop me. They should not win,” said Mari-Ann Wallander, who has been in the city centre several times during the day.

Sweden’s Security Service (Säpo) said it was working closely with Gothenburg police but the terrorist alert level remained unchanged.

The terrorism alert level was raised by one point in October from “weak” (two on a scale of five) to three because of the perceived increased threat of terrorism in Europe.