Group Keeps Long-Distance Watch on Iran and Possible Sanction Violations

Inside a nondescript Midtown Manhattan office, a couple of computer analysts spend their days peering intently at large screens of satellite mapping surveillance data, watching dozens of little blips moving like snails. Each one, they said, represents a ship controlled by Iran or its trading partners.

They said they were looking for suspicious behavior.

The analysts work for United Against Nuclear Iran, a privately financed advocacy group founded by former American diplomats that has become an annoying thorn to Iran, which regards it as a vigilante extension of a hostile American foreign policy. The group’s latest effort is its maritime monitoring system, which it says provides a new level of scrutiny of compliance with the sanctions imposed on Iran by the West because of Iran’s disputed nuclear energy program.

Although the economic and trade sanctions, including a European oil embargo, have deeply hurt Iran, the country has been somewhat successful in finding ways to evade them, the group says. A litany of clever tactics for cloaking commerce on the high seas has included reflagging, renaming or clandestinely acquiring ships, engaging in secretive ship-to-ship transfers to mask the origins of oil or other contraband, temporarily disabling onboard satellite transponders to hide their true locations or simply transmitting false destinations.

“Iran thrives on deception and disguise,” said Mark D. Wallace, the chief executive of United Against Nuclear Iran, who would like to see a maritime blockade.

Mr. Wallace said the recent Iranian presidential election, in which a cleric and former nuclear negotiator, Hassan Rowhani, was elected on a campaign promoting better relations with the outside world, had done nothing to alter his group’s view. “The regime has shown that it plans more of the same,” he said in a statement on the group’s Web site. “The world’s response should therefore remain the same — the continued isolation of Iran and comprehensive sanctions.”

Short of a blockade, he said in an interview, the maritime monitoring system, which has been in operation for about five months, has at least given Iran a new reason to worry.