The opposition gained another rallying point on Friday with the news of the death of another protester, this one with links to Iran’s political elite. Mohsen Ruholamini  whose father, Abdolhussen Ruholamini, is an adviser to another presidential candidate, Mohsen Rezai  died in custody at Evin prison after being arrested during demonstrations on July 9, opposition Web sites said, citing relatives.

Image Conservatives were opposed to Esfandiar Rahim Mashaei. Credit... Abedin Taherkenareh/E.P.A.

Mr. Ruholamini’s family had been told that he would be returning home, the Web sites reported. It was not clear how he died. The elder Mr. Ruholamini is a chemistry professor and the head of Iran’s Pasteur Institute. Mr. Rezai, a conservative and a strong critic of Mr. Ahmadinejad, is a former head of Iran’s Revolutionary Guards.

The news of Mr. Ruholamini’s death is likely to stoke anger further among the opposition, whose leaders say the number killed in protests since the election is much higher than 20, the figure the government provided.

The withdrawal of Mr. Mashaei ends a chapter that surprised and baffled many Iranians. A former culture minister whose daughter is married to Mr. Ahmadinejad’s son, Mr. Mashaei had reportedly said the Iranian people were friends with all other peoples, including Israelis. After a storm of criticism from conservatives, he disavowed his comments, saying he had meant only that Iranians sympathized with those living under the Zionist yoke.

Still, promoting him to presidential deputy was a risky move, especially considering that Mr. Mashaei had made other gestures that angered conservatives, including attending a ceremony in Turkey in 2007 where women performed a traditional dance.

“Maybe Ahmadinejad was trying to bolster his position vis-à-vis these political sharks” in the conservative establishment, who have long been critical of him, said Mehrzad Boroujerdi, an Iran expert and associate professor at Syracuse University.

In any event, Professor Boroujerdi added, the fierce conservative reaction suggests that “after the election crisis, not only reformists but hard-liners are smelling blood in the water and looking for concessions from Ahmadinejad.”