A concrete wall being built to stop illegal crossings along the length of Turkey’s 900-km (560-mile) border with Syria will be finished by the end of February, an official at a Turkish state institution with knowledge of the project said on Wednesday.Construction on a border wall to combat smuggling and illegal migration started as early as 2014 even as Turkey maintained an open-border policy that has seen nearly 3 million Syrians seek refuge in the country.