PHOENIX (AP) — Taser International is advising police agencies across the nation not to shoot its stun guns at a suspect’s chest.

The Arizona-based company says such action poses a risk — albeit extremely low — of an “adverse cardiac event.”

The advisory was issued in an Oct. 12 training bulletin. It marks the first time that Taser has suggested there is any risk of a cardiac arrest related to the use of its 50,000-volt stun guns.

Taser officials said Tuesday the bulletin does not state that Tasers can cause cardiac arrest. They said the advisory means only that law-enforcement agencies can avoid controversy if their officers aim at areas other than the chest.

Critics called it a stunning reversal for the company.