Tunisian anti-aircraft equipment seems to have be deployed near the southern borders with Libya, TunisianSoldier Twitter account said.
In these photos Swedish Bofors RBS-70 and a Zastava M55 Anti-aircraft gun.
The RBS 70 (Robotsystem 70, “robot” meaning “missile” in this context in Swedish) is a man-portable air-defense system (MANPADS) designed for anti-aircraft warfare in all climate zones and with little to no support from other forces.
The Zastava M55, also designated 20/3-mm-M55, is a Yugoslavian/Serbian 20mm triple-barreled automatic anti-aircraft gun developed in 1955 and produced by Crvena Zastava (now Zastava Arms company) in Serbia, for Yugoslav People’s Army use and also for the export market