Amnesty International has condemned a bomb attack on Thursday that left at least 16 civilians dead and dozens injured in the Russian republic of North Ossetia-Alania.
More than 70 people are reported to have been hospitalized, with at least 10 in a critical condition, after a car bomb exploded in Vladikavkaz, capital of North Ossetia-Alania, which borders Ingushetia in the North Caucasus.
The bomb reportedly exploded at the entrance to the central city market at 11.15am, just as scores of people were entering and exiting the market.
"An attack on people going about their daily business is a clear show of disregard of the right to life and the fundamental principles of humanity," said Andrea Huber, Europe and Central Asia deputy director at Amnesty International.
"The Russian authorities must immediately carry out a thorough and impartial investigation. The perpetrators of this heinous act must be brought to justice in line with international human rights standards."
No group has claimed responsibility for the attack. Media reports suggest that the car was driven by a suicide bomber.
The North Caucasus has faced instability for several years, with regular reports of killings of government officials by armed groups and suicide bombers targeting law enforcement officials and civilians.
Other parts of the North Caucasus such as Chechnya, Ingushetia and Dagestan have been most affected but there have also been reports of such attacks in North Ossetia-Alania in the past.
The Russian authorities' efforts to tackle violence by armed groups have often raised serious concerns about violation of international human rights law by police and security forces.
Cases of unlawful killings, extrajudicial executions, excessive use of force, enforced disappearances, arbitrary detention, torture and other ill-treatment in custody have been reported across the region.