Hundreds of Maoist militants killed at least 23 Indian security personnel in an ambush on Saturday in the central state of Chattisgarh.

At least 33 more Indian security personnel were injured in a five-hour-long shootout with the Maoists, also known as Naxalites. The Naxalites are a Communist militant group in India that has waged a violent insurgency against New Delhi since at least 2004. “The insurgents, who trace their roots to communist politics in the 1960s, use violence against the state in the name of championing the cause of India’s poor and marginalized,” the New York Times noted on Sunday.

“Inputs were received that Naxals [Naxalites] were undertaking their Tactical Counter Offensive Campaign (TCOC) … in the Jagargunda-Jongaguda-Tarrem axis [in Chattisgarh], and hence security forces teams from six camps [of the Indian military and police] were deputed to intercept them,” a senior Indian security officer told the Press Trust of India on April 4. “The Maoists drew the forces into an ambush with heavy gunfire soon after.”

“The Maoists rained bullets from light machine guns (LMGs) and used low-intensity improvised explosive devices (IEDs) to mount the attack,” the Times of India (TOI) reported Sunday.

The Indian forces “were attacked by over 400 Maoists from three sides. The ambush line stretched over 2 km [1.2 miles] near Tekulguda village. Running gunfights broke out near Tekulguda, Jonaguda, and Jeeragaon villages as the forces fought hard to break out of the ambush,” a survivor of the attack told TOI on April 4.

Roughly a dozen Naxalites died in the shootout and many stole weapons from fallen Indian forces. “Maoists looted weapons and even shoes from martyred jawans [Indian infantry soldiers],” a local police officer told TOI on Sunday.

“[T]he Maoists looted seven AK47s, two Insas rifles, and an LMG [light machine gun],” D.G. Kuldeep Singh India’s Central Reserve Police Force (CRPF) told the newspaper. The CRPF is India’s largest paramilitary force and specializes in targeting Left Wing Extremism (LWE) violence across the country, according to the Economic Times of India.

Indian Home Affairs Minister Amit Shah, who is responsible for Indian domestic security, confirmed the ambush on Saturday and flew to Chattisgarh on Monday to assess the situation and visit injured Indian forces in local hospitals.

“Our securitymen have lost their lives. We will not tolerate this bloodshed and a befitting reply will be given at an appropriate time,” Shah told Indian media on April 4.

“My thoughts are with the families of those martyred while fighting Maoists in Chhattisgarh,” Indian Prime Minister Narendra Modi wrote in a Twitter statement April 4. “The sacrifices of the brave martyrs will never be forgotten. May the injured recover at the earliest.”