About 4,000 people, mainly in their twenties, from the Middle East and Central Asia are now sleeping rough or staying in makeshift hostels close to Bosnia’s border with Croatia, most of them in Bihac and the frontier town of Velika Kladusa. Aid groups say the summer heat, squalid conditions and deepening desperation of migrants in Bosnia are increasing the threat to their health, as they take greater risks to enter Croatia. The migrants are also making more frequent reports of alleged beatings by Croatian border guards, which authorities deny. Bosnian has recorded the arrival of more than 9,000 migrants so far in 2018, well over 10 times the number counted in 2017. Of their numbers, several thousand are believed to have reached Croatia, many with the help of people smugglers. Most of the migrants arrive in Bosnia after crossing overland from Turkey to Greece and travelling through Albania and Montenegro. This route emerged following moves by several Balkan countries to shut their frontiers to migrants in March 2016, after more than a million migrants from the Middle East, Central Asia and North Africa crossed the region in frontiers to migrants in March 2016, after more than a million people from the Middle East, Central Asia and North Africa crossed the region in 2015.

Serif Grabovica was just five when late Yugoslav President Josip Tito in 1953 ordered a secret bunker to be built in Zlatar Mountain, near the town of Konjic, in what is today Bosnia and Herzegovina. Construction began in March of that year - hand-dug by companies of civilians contracted by the Yugoslav People’s Army (JNA). Workers never knew where they were or even what they were working on. Each day teams were transported blindfolded to-and-from site, along a back road east of town. Workmen entered through a nondescript house. Once inside, blindfolds were removed. The facility reaches 280 meters (920 feet) at its deepest point and built to survive a nuclear blast of 20-25 kilotons (Hiroshima, Japan in comparison, suffered a 15-kiloton nuclear attack in August 1945.). Two tunnels access more than one hundred rooms over a 6400 square-meter (70,000 square feet) horseshoe-shaped floor plan. Tito’s clandestine $4.6 billion facility was built to secure he, family and the lives of 350 of the country’s military and political elite. In 1979 - 26 years from its groundbreaking - the bunker was completed. Tito’s death came the following year, without ever a visit from the communist-era dictator. As a military conscript, Serif Grabovica served his country in those intervening years, rising to the senior non-commissioned rank of Sergeant Major. It was in 1979 that he and 14 other military men were sworn to secrecy over the bunker’s existence. Breakout of the Bosnian War in 1992 brought dispersal of this group, leaving Sargeant Major Grabovica entirely in charge of the facility. Commuting from his Sarajevo home two days a week, the Sargeant Major watched as its secrecy and partial inventory diminished. “Looting was a problem,” said Grabovica. “Medical supplies and surgical equipment quickly disappeared from the dispensary and operating room, carried away to field hospitals. Tables and chairs were lifted, too. I finally planted anti-personnel mines in the access ways to stop it,” he said. Then also in 1992 came the telephone order from High Command to destroy the tunnel completely, fearing its fall into enemy hands. “U redu, dobro gospodine. da gospodine” (“All right, good sir. Yes Sir”), was all the Sargeant Major replied throughout the call, captured on his tape recorder. To do the job, four-and-a-half tones of TNT were laid. But in the final minutes, Sergeant Major Grabovica disobeyed those orders, disconnecting the detonation wires and saving the multi-billion dollar object from obliteration. Today Tito’s nuclear bunker is the property of the Bosnian Ministry of Defence, and open to tour groups through specified tour agencies only. It is also venue for a modern art exhibition sponsored by the Association Biennial of Contemporary Art in Sarajevo.