"Iran and the Taliban are working well together to combat terrorism," says Iran's intelligence minister, Esmail Khatib.

In a video released on September 15 by the Iranian news agency Tasnim, which is close to Iran's Revolutionary Guards, Khatib claimed the West has driven the terrorist group known as Islamic State (IS) out of Syria and Turkey — and into northern Afghanistan.

"They have established themselves in mountainous areas where the Taliban government has little access and are carrying out attacks against members of the Taliban. We are working closely with the Taliban to take action against them," said Khatib.

An important Shia pilgrimage site in southern Iran has been the target of two deadly attacks in less than a year. In the latest attack, one person was killed and eight others injured on August 13 when a gunman opened fire in the Shah Cheragh mausoleum in Shiraz. In an earlier attack in October 2022, 13 people were killed and 30 wounded at the same site in an attack claimed by IS.

Long shared border between Iran and Afghanistan

"It's not only IS; other terrorist groups are also active in Afghanistan," says the security analyst Nisar Ahmad Shirzai. "These groups can also threaten neighboring countries and the region as a whole. IS and other terror groups could certainly pose a danger to Iran as well."

Iran has not officially recognized the Taliban as the government of Afghanistan. However, Tehran seeks to establish a pragmatic relationship with the rulers in Kabul.

Iran and Afghanistan share a border about 950 kilometers (590 miles) long that is difficult to secure. In places, it runs across high mountains and is not suited to deploying border guards.

Tehran maintained good relations with the Taliban long before they came to power. They found common ground primarily in the repudiation of the United States and its presence in the region.

"With the help of the Taliban, we have prevented terrorist attacks in the holy city of Mashhad," Iranian parliamentarian Mahmoud Nabavian told journalists in late August 2023 after traveling to Afghanistan.

Mashhad, Iran's second-largest city, lies less than 100 kilometers from the border with Afghanistan. Nabavian also said that there was extensive intelligence cooperation between Iran and the Taliban with regard to counterterrorism.

Evidence of Iranian inadequacy

Ali Afshari, an Iran expert in exile in the US, told DW that the repeated attacks in Shiraz were evidence of the Islamic Republic's inadequacy.

Afshari is a former student leader who campaigned for reform in Iran in the 1990s. He says that the recent terrorist operations show the Islamic Republic's propaganda claims about the strength of its intelligence and security agencies are just hollow boasts.

"These attacks show how fragile the country's protective shield against terrorism is," Afshari says.

"For more than ten years, Iran has been interfering in other countries in the region, claiming that it is implementing preventive measures to stop terrorism from penetrating the country. It is my belief that the jihadist Islamist groups, like IS or al-Qaeda, have not yet decided to stage large-scale attacks in Iran. If they do go down this path, there will be major catastrophes in the country."

Hussein Sirat contributed to this report.

The article was originally written in German.