Can pro-Mousavi protest movement keep up momentum after first death?

At least one person was killed by gunshots Monday, June 15, among the huge crowd of at least 100,000 which surged into Tehran’s main square in support of Mir Hossein Mousavi’s claim to have lost Iran’s presidential election on June 12 to the incumbent Mahmoud Ahmadinejad by fraud. At first, they quietly filled the squares and streets of Morth Tehran, defying the Iranian interior minister’s ruling that their assembly was illegal, in numbers comparable to the vast mass which cheered Ahmadinejad the day before. Their hero, Mousavi, appeared in public for the first time since the election and said he would be willing to run again in a new election.
Then gunfire was heard and the movement had its first death.
Until that point, Tehran apparently gave the movement some latitude hoping Mousavi’s supporters would tire if allowed to let of steam. Pushing another lever of control, supreme ruler Ayatollah Ali Khamenei ordered an investigation into the complaints that the election was rigged. He promised the panel would complete its work in 10 days.
Neither he nor any observers can say for sure whether or not the dissident movement can keep up the pressure of daily rallies – Velvet Revolution style – or how long a pretty ruthless regime’s patience will hold before it unleashes the police and Revolutionary Guardsmen against the crowds with perilous consequences.
Apparently braced for the next chapter in this extraordinary contest, Ahmadinejad postponed his visit to Moscow for scheduled talks with President Dmitry Medvedev Monday.