The country's Roman Catholic church hierarchy said in a statement Thursday that the violence showed that it couldn't yet resume a dialogue between protesters and President Daniel Ortega's government.
Cruz Sanchez and other mothers who make up the "Mothers of April" movement lamented that more people continue to die "because of the awful dictatorship" of Ortega that "dared" to send its mobs and police forces to attack the mass mobilization.
Francisco Diaz, the second in command of the national police, said there were 15 deaths nationwide, which he blamed on "criminal gangs".
Demonstrators burn the Sandinista radio station during clashes with riot police.
Recall, the protests began in mid-April, the reason for them was the reform of social insurance.
Ortega has been president of Nicaragua since 2007, and oversaw the abolition of presidential term limits in 2014.
Auxiliary Bishop Silvio Baez of Managua, who has received death threats for his support of the rights of people to protest, tweeted May 31 that the bishops" latest statement "does not speak generically of "violent acts" rather acts carried out by "groups related to the government against the civil population, ' "killing" the people".
The US State Department issued a statement condemning the "government's violent response to peaceful Mother's Day marches in Managua and other cities yesterday, including assaults on mothers mourning their children killed since protests began April 18".
Recently a group of mothers of those killed by pro-government forces were attacked at a protest by police and pro-government forces.
But Ortega on Wednesday vowed to remain in power, saying: "Nicaragua belongs to all of us, and here we are all going to stay". "We call on the state to stop the violence of these repressive factors", said Luis Almagro, Secretary General of the Organization of American States. The march ended in violence, as influential business leaders call for early elections to resolve a political standoff between Ortega's government and protesters demanding his exit from office.
"Unknown people continue to come to stalk our homes, continue to persecute us and harass us, we ask that they leave us alone when they are the cause of so much pain", said Graciela Martínez, sister of Juan Carlos Lopez Martinez, murdered in Ciudad Sandino on April 20 during the protests.