The victims were among 28 people on board a diving boat, the Wave Dancer, which sank in Independence, south of Belize City. Most of the victims were American tourists.
About 80,000 people were evacuated inland before winds of 220 km/h (140mph) and driving rain struck south-south-west of Belize City.
Iris caused flooding, destroyed crops and damaged houses, but rapidly weakened after hitting shore and was downgraded to a tropical storm with winds of around 60 km/h.
It was expected to continue to lose strength as it moved across the mountainous terrain of Guatemala and eastern Mexico during the rest of Tuesday.
Search for survivors
Helicopters and rescue boats conducted a major search and rescue operation after the US-chartered tourist boat sank. Eight survivors were found.
Patricia Rose, spokeswoman for Peter Hughes Diving in Miami, told the Associated Press that "a strong storm surge lifted the boat in the air, snapping the line and capsizing it".
"Belize City was evacuated so we could not put the guests in a hotel. We were forced to keep them on the boat," she added.
Grocery store owner Elizabeth Zabaneh in Independence said the hurricane had levelled the football stadium and collapsed
the only hotel in town.
"There's so much damage here I can't even begin to explain it," she told the Associated Press.
"There are telephone polls in the streets. Bananas that were in containers on the docks are everywhere, all crushed. Seventy percent of the buildings don't have roofs. There are collapsed buildings and flattened cars."
Houses destroyed
The governments of Honduras, Mexico, Guatemala and El Salvador lifted their earlier hurricane warnings along coastal areas.
Iris gained force while passing Jamaica on Sunday, while three people were killed in torrential storms in the Dominican Republic.
About 5,000 Guatemalans were evacuated from their homes on the Caribbean coast.
In Belize, a steady stream of traffic headed out of coastal areas as inhabitants fled inland, taking their personal possessions with them.
In Belize City, north of the storm, thousands of soldiers went door to door evacuating residents.
The nation's capital was moved inland to Belmopan after much of Belize City was destroyed by Hurricane Hattie in 1961.
Recent devastation
Memories are still fresh in the region of the deadly trail of destruction left behind by Hurricane Mitch three years ago this month.
Some experts have warned that Hurricane Iris could head inland and then suddenly change course as Mitch did, causing major rivers to swell and break their banks in a matter of just a few hours.
Central America is still reeling from the effects of a three-month drought earlier this year which devastated crops and left many poor farmers destitute.
Related to this story:
Belize surveys hurricane aftermath
(10 Oct 01 | Americas)
Hurricane Iris threatens Caribbean
(07 Oct 01 | Americas)
Mexico's deadly hurricane eases
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Decades of major hurricanes ahead
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Hurricanes set to grow fiercer
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Internet links:
US National Hurricane Centre |
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