(This April 25 story corrects third paragraph with attribution to Russia's Interior Ministry, not to Stavropol authorities)
By Jason Bush
MOSCOW (Reuters) - Russia announced on Saturday it would investigate the shooting dead of a Chechen that has highlighted tensions between central police authorities and a hardline Chechen regional leader brought in by President Vladimir Putin to quell separatism.
Police from the neighboring Stavropol region shot a man dead in the Chechen capital Grozny last Sunday, infuriating regional leader Ramzan Kadyrov, who urged his own police to "shoot to kill" if officers from outside Chechnya acted there without permission. Russia's Interior Ministry responded by calling his comments "unacceptable".
The ministry said the man had been on the run after a shooting incident.
Kadyrov professes loyalty to Putin but enjoys a large degree of autonomy to run his mainly Muslim region. The former amateur boxer has ruled Chechnya since 2007, bringing relative peace to a region racked by two separatist wars, but drawing criticism from human rights groups because of his heavy-handed methods.
In a potential headache for Putin as he tries to balance rival factions in his power structure, resentment against Kadyrov also appears to be building up among top law enforcement officials in Moscow - and vice versa - as a result of turf wars over their respective authorities.
Underlying all this is Moscow's attempts to restore stability throughout the north Caucasus region, where Islamist militants have been operating.
On Saturday, Russia's Investigative Committee, the top investigative body, issued a statement saying it would carry out a "procedural check" into the incident. Russia's chief investigator had earlier canceled a local criminal investigation into the incident.
"The people of the Chechen Republic are asking why the probe was canceled, if it was based on suspicions of deliberate killing," Kadyrov said on his Instagram account.
Tensions first surfaced after the Moscow shooting in February of leading opposition politician Boris Nemtsov, which has provoked a tangle of conflicting accounts and conspiracy theories, often involving Chechnya.
Police have charged a former commander in Kadyrov's police with Nemtsov's murder. Some observers have said that the arrest of a Chechen with links to Kadyrov illustrates how, in the eyes of federal law enforcers, Kadyrov has overstepped the mark.
Russian media have reported incidents of police in Moscow having run-ins with Chechens, then coming under pressure not to prosecute them because of their ties to Kadyrov.
Adding to the intrigue, the man recently killed by police, Dzhambulat Dadayev, shares a surname with Zaur Dadayev, the former Chechen police commander charged with Nemtsov's murder.
Kadyrov said the two Dadayevs were not related or connected.
(Reporting By Jason Bush)