Last week, Syria test fired two Scud type ballistic missiles. The guidance systems on both of them were not working properly. One of the missiles landed in the market place of a village near the Turkish border, killing twenty people and injuring at least sixty. At first, the government said it was a natural gas explosion, but the truth soon came out (it's kind of hard to hide the missile debris, and a Scud impact is quite different from a natural gas explosion.)
It also came out that Syria was testing a new version of the Scud, designed in cooperation with Iran and North Korea. In any event, Syria has been testing its ballistic missile inventory a lot in the last 18 months, with several dozen missiles fired. Israel has made no secret of the fact that, in a future war with Syria, they estimate that there would be as many as 3,300 Israeli casualties (including up to 200 dead). That's if Syria just used its long range missiles armed with conventional warheads (high explosives or cluster bombs). If the Syrians used chemical warheads, Israeli casualties could be as high as 16,000. Over 200,000 Israelis would be left homeless, and it's believed about a 100,000 would seek to leave the country.
Syria has underground storage and launch facilities for its arsenal of over a thousand SCUD missiles. Armed with half ton high explosive and cluster bomb warheads, the missiles have ranges of 500-700 kilometers. Syria also has some 90 older Russian Frog-7 missiles (70 kilometer range, half ton warhead) and 210 more modern Russian SS-21 missiles (120 kilometer range, half ton warhead) operating with mobile launchers. There are also 60 mobile SCUD launchers. The Syrians have a large network of camouflaged launching sites for the mobile launchers. Iran and North Korea have helped Syria build underground SCUD manufacturing and maintenance facilities. The Syrian missiles are meant to hit Israeli airfields, missile launching sites and nuclear weapons sites, as well as population centers. Syria hopes to do enough damage with a missile strike to cripple Israeli combat capability.
Israel has long been aware of the Syrian capabilities and any war with Syria would probably result in some interesting attacks on the Syrian missile network. The SCUD is a liquid fuel missile and takes half an hour or more to fuel and ready for launch. So underground facilities are a major defensive measure against an alert and astute opponent like Israel.
It is feared that the recent Syrian tests are partly training exercises to see how ready the missile launcher crews are. Some of the tests are also testing new guidance systems, perhaps using GPS or Russian Glonass to attain high accuracy. Syria has been working more closely with Russian and North Korean military suppliers lately, and has been a client state of Iran for over two decades.