BRUSSELS: NATO's Patriot anti-missile defense batteries along Turkey's border with Syria will become operational this week, a senior official said Wednesday.

Patriot batteries sent by the United States, Germany and the Netherlands have reached Turkey and are being deployed in the south of the country, said British Brig. Gen. Gary Deakin. The U.S.-made missiles are designed to protect Turkey, a NATO member, from any possible incoming ballistic missiles from Syria, where civil war has left at least 60,000 people dead.

"We expect to have an initial operating capability this weekend" with full operations by the end of the month, Deakin told reporters.

"We estimate that once it is in place at those locations, we will provide protection against missiles for up to 3.5 million people," Deakin said, adding that NATO was planning to keep the batteries in Turkey for at least a year.

Syrian President Bashar Assad's regime is believed to have hundreds of artillery rockets, as well as short- and medium-range missiles - including Soviet-built SS-21 Scarabs and Scud-B missiles - in its arsenal. The latter are capable of carrying chemical warheads.

Although Syria is reported to have used tactical surface-to-surface rockets against rebel forces on several occasions in the nearly two-year civil war, none has landed inside Turkey.

Syria's conflict started in March 2011 as an uprising against Assad, whose family has ruled the country for four decades but it quickly morphed into a civil war.

More than 1,000 American, German and Dutch troops are to be based in Turkey to operate the six Patriot batteries.

The Americans will be based at Gaziantep, 50 kilometers (31 miles) north of the Syrian border. The Germans will be based at Kahramanmaras, 100 kilometers (60 miles) north of the Syrian border and the Dutch at Adana, 100 kilometers (66 miles) west of the border.

The Patriot missiles, which first entered service three decades ago, have been successively upgraded over the years. Although mostly used for anti-aircraft defense, advanced versions can also be used against cruise missiles and medium- and short-range ballistic missiles. They have a maximum range of about 160 kilometers (100 miles) and can reach altitudes up to 80,000 feet.

NATO has repeatedly said the deployment in Turkey was strictly defensive and that the Patriots would not be used to establish a no-fly zone over northern Syria.