"The most terrifying of all Iranian missiles is the Sejil long range missile. It has commonly been considered merely a surface-to-surface missile, but the armed forces recently announced that it can also be used to destroy naval targets. Although not much is known about the missile's guidance and targeting systems, the missile has shown great accuracy in hitting a predetermined target. This missile, with a range of 2,000 km, can reach speeds of Mach 8 to Mach 12 (2,700-4,100 meters per second)... Its warhead weighs at least 500 kilograms, helping it to destroy the target. This missile can be used to cover regions beyond the Strait of Hormuz even if deployed on the northern Iranian coast, or at the most distant point in northwest Iran. It is a two-stage rocket powered by solid fuel, and reaches great speed at the end of the first stage [of launch]. It is difficult for the enemy to detect and track it during the first stage, because it uses several methods to reduce its radar signature... Thanks to its high velocity, the chance of it being hit by enemy defense [systems] is even smaller than the chance that they will hit a Khaleej-e Fars missile.
"Such missiles would be launched from deep inside Iranian territory because scattering launchers over a larger area will make it difficult for the enemy to detect them, will limit the means the enemy will be able to use to destroy them, and will also allow the launchers to be relocated and re-camouflaged.
"Although the enemy is much more likely to detect lower-velocity missiles... the combination of the use of these weapons in areas both closer and farther away from the shore and the increased number of targets... can maintain their effectiveness."
source:
http://www.memri.org/report/en/0/0/0/0/0/0/5956.htm