GROZNY — Chechen women said police had targeted them with paintball pellets for not wearing headscarves, outraging rights activists.

The attacks highlight tension over efforts by Chechen President Ramzan Kadyrov to enforce Muslim-inspired rules that in some cases violate Russia's Constitution.

"A car carrying men in military uniform slowed down to approach us, one started filming on his mobile phone, and when they sped away we noticed paint all over our clothes," a woman in Grozny said on condition of anonymity Friday.

Several witnesses told Reuters that men in camouflage, which is worn by many Chechen police and security officers, had fired paintball guns at women from cars with tinted windows in multiple incidents this month. A spokesman for the Interior Ministry, which handles the police force, declined to comment Friday about the reports.

"This paintballing is an obvious Kadyrov rule just used to strengthen and tighten his grip over his tiny republic," said prominent human rights activist Lyudmila Alexeyeva, who heads the Moscow Helsinki Group.

Rights group Memorial, citing witnesses, said in a statement that it believed police were behind the attacks that fired the paint at women's faces and necks. Local media said there were about 12 such attacks.

Fliers from the self-proclaimed paintballers appeared last week in the city of Gudermes, site of Kadyrov's opulent residence, warning women that if they did not cover their heads the attackers will be "forced to resort to tougher measures."

"Isn't it nasty for you, while dressed defiantly, with your head uncovered, to hear various obscene 'compliments' and proposals? Think again!" it read, according to a copy posted on the Caucasus Knot news web site.

Police also declined to comment on the fliers, some of which were posted on state buildings and bus stops.