At least two police officers were killed in Ingushetia on April 5, after a suicide bomb went off near a police headquarters there.
Less than an hour after the attack, a second bomb in a car opposite the police station was detonated, wounding an investigator from the local prosecutor's office.
The attacks came as Russian authorities continued their hunt for those responsible for twin suicide attacks on Russia's Moscow metro on March 29, that killed 40 people.
The so-called Caucasus Emirate, an Islamist group led by Doku Umarov, a Chechen anti-government commander, claimed responsibility for the metro attacks.
Those attacks were followed by suicide bombings in the Dagestan region of the North Caucasus that killed 12 people, including a local police chief.