Former Mexican President Luis Echeverria has denied any wrongdoing about his alleged role in two student massacres more than 30 years ago.
For the second time in eight days, Mr. Echeverria spent several hours Tuesday before a special prosecutor, who read a document accusing him of involvement in the deaths of student protesters.
The prosecutor has given Mr. Echeverria at least 150 questions. The former president must respond to them within 40 days.
Wednesday's questioning involved allegations about the 1971 slaying of dozens of students believed to have died when government forces opened fire during a student protest. Mr. Echeverria was president at the time.
The former president also appeared in the court last week. That hearing focused on the 1968 massacre of protesters in Mexico City when Mr. Echeverria was interior secretary in charge of domestic security. Those demonstrations occurred just days before the city hosted the Summer Olympics. Government reports put the death toll at 30, but human rights groups say as many as 300 people died.
Mr. Echeverria told reporters his conscience was clear about his involvement in both incidents.