Several protests loosely organised around the slogan "No to Serzh", have been held since March. Protesters have been gathering in front of the ruling Republican Party's headquarters since 9 April, when acting Prime Minister Karen Karapetyan announced that Serzh Sargsyan would replace him.
The Ministry said some have already been discharged from medical institutions. The parliament is expected to vote Tuesday on the matter.
On the same day, protesters led by Pashinyan seized the building of Armenia's Public Radio for around an hour.
Several hundred people sat or laid down on pavements on Monday, blocking roads leading to the parliament building and universities.
Seven Killed, 17 Injured In United States' Prison Riot
Lee County Fire & Rescue says multiple agencies were called into assist with the "mass-casualty incident" at the prison. In March, inmates at the prison held an officer hostage after taking control of a dorm room, The State reported.
"Something unprecedented is happening in Armenia - the same person wants to become the country's leader for a third time", Pashinian said at the weekend.
Armenia's opposition views the move as Sargsyan's attempt to stay in power indefinitely and has vowed to keep protesting around the clock. Some built barricades using cast-iron benches and metal trash cans.
Rallies began on Friday with more than four thousand taking part.
Armen Sarkisian took over as president from Sargsyan on Monday under a new system in which the president's powers will be weaker and the prime minister will dominate. After Sarkisian was first elected president in February 2008, 10 people died in bloody clashes between police and supporters of the defeated opposition candidate.