Ghulam Dastagir Azad, the governor of Afghanistan's southwestern province of Nimroz, told RFE/RL's Radio Free Afghanistan that one of the detained men was captured with documents and photographs that prove he had links with militants.
Azad said the man was captured trying to enter the city of Zarang, on the border with Iran. "He had a camera that had photographs of weaponry indicating clear ties with [Afghanistan's] enemies," Azad said.
In a second incident, near Afghanistan's southeastern border with Pakistan, authorities say they detained an Iranian man who was preparing information for what they believe was an attack against NATO and Afghan security forces.
No Passport, Documents
Wazir Pacha, the assistant police chief in the southeastern Afghan province of Khost, said the man was not carrying any passport or documents and that he initially had pretended to be mentally ill. But Pacha says the man later confessed that he was on an information-gathering mission.
Police in Khost played an audio recording for journalists in which the man confesses he was preparing maps of NATO and Afghan military installations in Khost, which lies just across the border from Pakistan's volatile tribal region of North Waziristan.
In that recording, the man says he is from the town of Shiraz and entered Afghanistan from the Iranian border city of Mashhad. He says he arrived in Khost after passing through the Afghan cities of Herat and Kabul.
Meanwhile, Afghan security forces say they discovered a large cache of weapons in the western Afghan province of Herat, just 10 kilometers from the Iranian border. Authorities say they suspect the weapons were sent from Iran and were intended for the Taliban.
Ramatullah Safi, chief of border police in western Afghanistan, told Radio Free Afghanistan that some of the weapons contained Iranian markings.
"The cache contained one mortar shell, 785 land mines, and 445 tripod-mounted machine guns," Safi said. "There also was a lot of ammunition -- 2,400 boxes of ammunition for Kalashnikov assault rifles, 85 rocket-propelled grenades, and other ammunition."
'Interfering' In Different Ways
The Afghan government has not commented on the significance of the arrests or the discovery of the weapons cache. But Richard Boucher, the assistant U.S. secretary of state for south and Central Asia, told reporters in Paris on May 6 that Iran is interfering in Afghanistan in "a variety of different ways -- perhaps not as violently as they sometimes do in Iraq."
Boucher concluded that Iran is seeking to keep Afghanistan weak and unstable by delivering weapons to the Taliban while ostensibly supporting the central government of Afghan President Hamid Karzai. He said Washington sees "Iranian interference politically" in terms of money that Tehran channels into Afghanistan's political process, as well as interference aimed at undermining the Afghan state by playing off local Afghan officials against Karzai's government.
Radio Free Afghanistan correspondents Sharafuddin Stanakzai and Reshtin Qadiri in Herat; Amir Bahir in Khost; and Ajmal Seddique in Prague contributed to this report