The bombing, which gutted the Ingushetia province building as police arrived for a shift change, was the deadliest in years in Russia's restive southern region, calling into question Kremlin assertions that the area was stabilizing after two wars in Chechnya and mounting violence in surrounding provinces since 1994.
Police fired at the truck, but failed to stop it before it exploded about 9 a.m. local time in the middle of the courtyard, leaving a huge crater and a raging fire that spread to an ammunitions cache in a weapons room, the Associated Press reported.
It took rescue teams several hours to search for victims in the rubble. An adjacent apartment building and several office buildings were also damaged.
Aslan Ozdoyev, a spokesman for the Emergency Ministry's branch in Ingushetia, told the AP that 118 people were injured and about 100 of them were hospitalized. At least 10 of the injured were children.
Russia's Emergency Ministry dispatched a large plane to an airport in nearby Beslan - site of the 2004 school massacre - to transport some of the wounded to Moscow for treatment.
The investigative wing of the prosecutor general's office said the death toll was expected to rise, according to the New York Times. President Dmitri Medvedev ordered the nation's interior minister to increase the number of police forces in the province.
Ingushetia, which borders Chechnya, has seen a epidemic of shootings, bombings and other attacks on police and government. While most of the fighting in Chechnya has waned, Islamic militants have continued hit-and-run attacks and skirmishes in neighboring provinces.
Less than a week ago, masked gunmen shot and killed Ingushetia's construction minister.
The Kremlin-appointed president of Ingushetia, who was badly wounded two months ago in another suicide bombing, said Monday's attack had been organized by militants trying to avenge recent security sweeps in the forests along the mountainous border with Chechnya.
"It was an attempt to destabilize the situation and sow panic," Yunus-Bek Yevkurov said in a statement issued through his spokesman, according to news agencies.
He blamed Chechen separatist warlord Doku Umarov for the June attack on his convoy, saying the perpetrators had been tracked down, according to an interview with Russian News Service radio. He vowed to hunt down Umarov and other rebel warlords.
He also accused the United States, United Kingdom and Israel of fomenting instability in the North Caucasus, saying "the West will try to prevent Russia from restoring its Soviet-era might," the AP reported. He did not elaborate.
Human rights activists and Ingushetia opposition politicians told the BBC last year that the republic was in a situation of "civil war."
---- Compiled from wire reports and other media sources