The Spanish government and opposition blamed each other on Monday after crowds of mostly maskless youths partied in the streets of Madrid and Barcelona at the weekend.
The parties came when a state of emergency imposed to curb the Covid-19 pandemic ended at the weekend.
Imposed last October amid an alarming second wave of infections, the state of emergency allowed the temporary suspension of some civil liberties, including a nationwide curfew and local travel bans.
Its expiry, partly because the minority government of socialist prime minister Pedro Sanchez would struggle to win a majority in parliament to prolong it, spurred celebrations as well as concerns that such behaviour could lead to another spike in cases.
Crowds of several hundred people breached rules on social distancing and mask wearing in public, and in some cases police moved in to break them up and fine some individuals.
"The absolute irresponsibility of the government of Sanchez costs lives," said Pablo Casado, leader of the conservative People's Party, added that the opposition wanted a new law that would allow regions to maintain restrictions.
For its part, the government blamed the opposition, including conservative leader of the Madrid region, Isabel Diaz Ayuso, who has just won re-election thanks in part to a relatively relaxed approach to coronavirus restrictions.
"When you spend months and months and months sowing false freedom in the citizenry... that's what you get," senior government official Mercedes Gonzalez told Cadena Ser radio, referring to maskless partying in the streets of Madrid.
Now that the state of emergency has expired, each of Spain's 17 regions has to individually ask courts to approve any restrictions they see as necessary for their territory.
And the government said regions had the option of asking for a state of emergency to be reinstated locally if needed.
"... no one is giving up on their responsibilities or abandoning regional governments," Justice Minister Juan Carlos Campo said in an op-ed in El Pais, hitting back at critics and saying a nationwide state of emergency was not necessary anymore.
Meanwhile, medics voiced concern that such celebrations could set the country back after more than a year fighting a disease that has at times overwhelmed Spain's health system.
Spain has reported close to 79,000 deaths from Covid-19 and more than 3.5 million cases since the beginning of the pandemic. But the number of cases per 100,000 people over 14 days has fallen to 199, from 523 in mid-January.
"Saturday night's images are deeply saddening after the hard and difficult year we have been through," said Javier Millan, a spokesman for Spain's ER doctor's association SEMES.
Nurse Rafael Fernandez Castillo said on Twitter: "On my way to the hospital, I run into several groups of people without a mask, but with a glass in their hand. I arrive to the ICU and there are no free beds."