There is, likely, Iranian tactical support and training that is helping them.
That is also true.
No link found in Iraq helicopter crashes: Pentagon
WASHINGTON (AFP) - The US military has not established a link connecting the five helicopter crashes in Iraq over the past three weeks, a Pentagon spokesman said.
"Clearly, each time we have an aircraft go down, we take a look at it, and given the proximity of these events happening together, we'll have people looking at them not only as individual events but collectively, as to whether or not there is any correlation," spokesman Bryan Whitman told reporters.
Asked whether the frequency of the crashes meant that insurgents were better armed, Whitman said: "I don't think I can make any sort of conclusion like that at this point."
On Wednesday, the US military said seven crew members and passengers died when a US Marine helicopter crashed in Al-Anbar province, a Sunni Arab insurgent bastion west of Baghdad, earlier in the day.
Officials are investigating what caused the crash. Whitman said they have not yet indicated whether the cause was "mechanical, human (or) hostile."
The crash brings to five the number of US helicopters that have crashed in Iraq in less than three weeks.
On Sunday, the US military revealed that four US helicopters which had crashed since January 20, killing a total of 20 troops and private security guards, had been shot down by insurgents.
http://news.yahoo.com/s/afp/20070208/pl_afp/usiraqunrest_070208175836;_ylt=AoYtpU_StZ7vbIcI8fsymhYUewgF