Lebanon has discovered an additional 4.35 tons of ammonium nitrate near the Beirut port, where last month a large stockpile of the same hazardous material touched off the explosion that gutted the city.  

Customs officials asked the Lebanese army to inspect four containers outside the port, state agency NNA reported today. The army is now “dealing with it,” suggesting engineers are destroying the chemical or moving the containers to a safer location. 

The discovery came nearly a month after the Aug. 4 blast, which killed at least 190 people, injured roughly 6.000 and left nearly 300,000 homeless. Lebanese authorities say the explosion was caused by some 2,700 tons of ammonium nitrate, a chemical commonly used in agricultural fertilizers, that was stored unsafely at Beirut’s port for six years. 

Within days of the blast, cleanup teams had identified 20 containers filled with possibly dangerous chemicals that were then moved to a safe location. Twenty-five people have been arrested in connection with the explosion, most of whom worked at the port or in customs.