Syrians fleeing the war in their country are at risk of being killed or maimed by landmines placed along parts of Turkey’s border decades ago.

A Syrian teenager in the Turkish city of Sanliurfa told Al Jazeera how he lost both his legs and his brother when he and his family headed for the border fence with Turkey, straying into a minefield.

"Someone told us to cross under the border wire. As we did a mine exploded under my brother and me. My brother was killed. I lost my legs," said 13-year-old Fadil Mustafa.

Fadil and his family were among thousands of Syrians fleeing the advance of the Islamic State of Iraq and the Levant (ISIL) group that has seized large swathes of territory in Syria and Iraq.

Fadil's father said he feared that the injury had ruined his son's future.

"What future can you expect for a 13-year-old who has lost his legs? We all have no future ... We lost all of our property that we built up over 50 years," said the father, identified only as Mustafa.

Last month, Human Rights Watch said landmines placed by the Turkish military had killed at least three civilians trying to flee Syria and injured another nine others.

Thousands of Syrians have crossed through mined territory since ISIL advanced on the majority-Kurdish border town of Kobane in mid-September.

In just four days, more than 130,000 people fled to Turkey.

Thousands at risk

The New York-based group said the landmines, in a restricted zone along the border with Syria, threaten thousands more Syrian refugees.

It said it interviewed one Syrian Kurdish woman who stepped on a mine after she entered Turkey, badly wounding herself and her seven-year-old daughter. She said she did not see any signs warning that there were landmines in the area.

The Turkish government says there are more than 600,000 mines along Turkey’s 900km border with Syria, placed there to prevent illegal border crossings.

Haldun Solmazturk, a retired Turkish army brigadier-general, who was involved in laying mines on the border, told Al Jazeera that Turkey started placing mines there in the 1950s when the country became a NATO member and Syria was considered a proxy of the Soviet Union.

He said the size of the mined area is "two times the island of Cyprus and it would take years to clear it".

Turkey joined the landmine ban treaty in 2003, but it was slow to start clearing and fencing off mined areas and then the war in Syria started.

The government says it is now too dangerous to start clearing the hundreds of thousand of mines that divide the two countries.

"I find what happened to this boy heartbreaking," said the mayor of Sanliurfa city, Izzettin Kucuk, referring to Fadil who lost his limbs. "But because of the fighting, it wasn’t possible to clear the minefield."