Demonstrators massed at a funeral for an opposition political activist killed by Paraguayan police after an anti-government break-in at Congress.
Rodrigo Quintana, 25, leader of the Liberal Party's youth branch, has become the unwitting symbol of deep frustration with conservative President Horacio Cartes' bid to restore politicians' ability to run for re-election.
Quintana was shot and killed as police searched the party's offices in Asuncion after street riots broke out late Friday.
At the funeral Sunday in this town southeast of the capital, one of Quintana's young daughters carried a photo of her father, who was just about to graduate as an agronomist.
Supporters waved a banner reading "Quintana martyr of freedom and democracy."
"Enough of the violence," priest Osvaldo Caniza said in the sermon.
Furious protesters broke into the Congress late Friday, ransacking lawmakers' offices and starting fires, after senators approved a proposal to allow the president to run for re-election.
Opposition leaders denounced the secretive vote Friday as a "congressional coup," saying it could clear the way for a return to dictatorship in the landlocked South American nation of 6.8 million people.
Cartes is seeking to amend the constitution to enable himself to run for office again in 2018 after his current term ends.
He blamed the violence on "a group of Paraguayans embedded in politics and the media aimed at destroying democracy and political and economic stability."
"Democracy is not won or defended by violence," he said on Twitter.
Paraguay has banned presidents from re-election since 1992 to avoid a return to dictatorships like that of General Alfredo Stroessner, who ruled from 1954 to 1989.
Removing the ban would also allow left-wing former president Fernando Lugo to run again. He held power from 2008 to 2012, when he was removed after an impeachment trial.
The measure was scheduled to be considered Saturday in the Chamber of Deputies, where the president has a majority.
But after the unrest, the president of the lower house, Hugo Velazquez, announced the vote was postponed, saying he was shocked by the violence.
If the latest measure is approved by the two houses, it is expected to be put to a referendum within three months.