The U.S. Department of State issued an advisory late Monday warning travelers against visiting southeastern Turkey amid regional tensions in the region. It asked American citizens to particularly avoid traveling to areas near the Syrian border.

“Recent terrorist attacks from international and indigenous groups have targeted popular tourist sites, U.S. government buildings, police, and other local authorities throughout Turkey. The threat of kidnapping remains a concern, especially in the southeast. There have been incidents of cross-border shelling from Syria into Turkey,” the bulletin said. Travel restrictions continued for U.S. government employees against visiting the several provinces and cities in the country’s eastern and southern regions.

Turkey has stepped up security at its border as a measure to tackle the growing influx of insurgents from Syria in recent months. Turkey has been repeatedly targeted by the Islamic State group and Kurdish rebels.

Last month, at least 28 people were left dead and 61 injured following a large explosion in Turkey's capital Ankara. In January, Kurdish rebels from Kurdistan Workers' Party (PKK) targeted a police station in southeastern Turkey with a car bomb, killing at least five people. The blast also damaged nearby residential buildings. Extremists have carried out several attacks in Turkey, including suicide bombings in Ankara in October that resulted in more than 100 deaths.

Turkey is weighing the possibility of buying Medium Extended Air Defense System following recent attacks in the country. Turkish industry sources told Defense News that Ankara wanted to develop MEADS domestically, but it will have to import the components because of the immediacy of the purported risks. The MEADS is jointly developed by the United States, Germany and Italy, and is capable of providing 360-degree protection from ballistic missiles, cruise missiles, aircrafts and rockets.