Two Iranian border guards and one Taliban fighter were killed during armed clashes near a border police station between Iran and Afghanistan, according to Iran's official IRNA news agency and the Taliban's Interior Ministry on Saturday.

The two sides accused each other of opening fire first on Saturday morning near the police station on the border of Iran's Sistan and Baluchestan province, and the Afghan province of Nimroz.

The reason for the skirmish is not known yet, and the Iranian Embassy in Kabul and Afghanistan's Taliban-run acting Ministry of National Defense have started correspondence and phone calls to investigate the cause of the tension.

The conflicts also led to the injuries of several others from both sides, including civilians, according to the IRNA and the Taliban's Interior Ministry.

According to Iran's semi-official Tasnim news agency, the two sides used "light and semi-light weapons and artillery" against each other, but no missile was employed by the Iranian side as claimed by some "false" reports.

The clashes came as tensions between the two neighbors have escalated during the past few weeks over Iran's "unpaid" water share from the Hirmand River, known as Helmand in Afghanistan, under a 1973 treaty between Tehran and Kabul that entitles the former to receive 820 million cubic meters of water from the river per year.

In remarks on Thursday, Iranian Foreign Minister Hossein Amir-Abdollahian said that his country does not recognize Afghanistan's caretaker Taliban government and insists upon the formation of an inclusive government in the country.

The Taliban government also issued a statement last week, saying Iran's frequent requests for water and "inappropriate" comments on the media are "harmful," adding that it is committed to the 1973 treaty.