Spain's acting interior minister, Fernando Grande-Marlaska, has insisted authorities are not overwhelmed after more violence in Barcelona on Friday.
Masked demonstrators clashed with police in the centre of the Catalan capital for the fifth consecutive day.
The violence is linked to the sentences handed down this week to Catalan separatist politicians over the 2017 independence referendum.
But other mass rallies held across the city and region to denounce the prison terms to nine independence leaders were peaceful.
The violence on Friday saw 182 protesters and 101 police injured, according to authorities.
Grande-Marlaska said on Saturday the situation in Catalonia "is being controlled". He also claimed that the state is not "overwhelmed" by the tense situation that the region is going through since last Monday.
"I very much regret that there are injured demonstrators, and at the same time we are not going to tolerate physical aggression against police, mosos (Catalan police) and civil guards (military police). I cannot remain impassive in the face of vandalism in some localities of Catalonia."
Grande-Marlaska's comments were made after travelling to Barcelona to meet his regional counterpart on Saturday, Miquel Buch, as well as the police commanders in charge of the security operations in the region.
"There is an important, serious, organised and commanding violence, but I reiterate that we are not overwhelmed. This is a situation of serious public order, to which the state is responding", Grande-Marlaska said.
After the meeting with Buch, Marlaska claimed that his visit to Barcelona was "first and foremost" to acknowledge the "high personal cost" of the police.
"Coordination between police forces is extraordinary," he said. "It does not matter the colour of the uniform, but their willingness to guarantee the rights of the citizens."
On Friday, a crowd of protesters hurled stones and cans at police in riot gear, and dragged large garbage bins to the middle of a main city boulevard, and set them ablaze. Police vans tried but failed to push people back onto the pavements.
The president of Catalonia's regional government Quim Torra, called for "responsibility" after Friday's violence but has not explicitly condemned the violence.
On Friday, a Spanish judge ordered the closure of a secretive Catalan protest group's website as authorities scrambled to find who is behind street demonstrations.
Attention has focused on "Democratic Tsunami", a new group that emerged last month and quickly gained a huge social media following.
Its main action was a massive protest at Barcelona airport on Monday, which caused dozens of flight cancellations.
Earlier, FC Barcelona and Real Madrid's La Liga game in Barcelona due to be played on October 26 was rescheduled to December 18 amid the unrest.
Why was Barcelona on fire in the first place?
Tensions between Catalonia and the Spanish central government have been rising since Monday, when Spain’s Supreme Court sentenced nine politicians and activists to up to 13 years in jail over their role in a failed 2017 independence bid.
The sentences set off protests across the region, with demonstrators at times clashing with police. Barcelona town hall said 400 garbage containers were set ablaze during protests on Wednesday and estimated that the city had suffered damage totalling more than 1 million euros in two days.
Pro-independence leaders went ahead with a 2017 referendum on independence, despite it being deemed illegal by Spanish courts, followed by a declaration that the region was breaking away from Spain. Madrid responded by seizing control of the Catalan administration and putting the ringleaders on trial.