The owner of the Laleena, Rat Chuped, said the team of about eight officers turned up without warning. She thought they were from the provincial Public Health office.
They took samples from ground-floor Rooms 4 and 5 at the guesthouse.
The two dead tourists, one an American and the other a Norwegian, fell ill in the adjoining rooms on May 2.
Jill St Onge, 27, from Seattle, and Norwegian Julie Michelle Bergheim, 22, showed similar symptoms and died within hours of each other at the local hospital.
''I was not told the officials were coming,'' Khun Rat said today. ''They did some work on the air-conditioning units and took away the filters, I think.''
Khun Rat has rejected a suggestion that she should close her guesthouse.
''That won't bring the two women back. As far as I am concerned, there is no problem with my guesthouse,'' she said.
''If I close Laleena, how am I going to put food on the table?''
Khun Rat says she has since slept in one of the rooms where the dead women were staying and is confident her guesthouse has no connection with whatever caused the two deaths.
Two guests remain at Laleena. They are relatively new guests, although at one stage earlier this month, Khun Rat said she would probably only keep the guesthouse open for the customers who were there at the time.
Speculation continues about the cause of the deaths. Toxicology tests on tissue samples taken from the bodies are being carried out in Bangkok.
Khun Rat told Phuketwan today that one of the investigating officers said on Saturday that the results could take many weeks.
Laleena has 10 rooms, five of them air-conditioned. Guests on the first floor, above Rooms 4 and 5, and in rooms at the rear, suffered no ill effects that day or night.
Khun Rat, her housemaid and two children slept in a room nearby, closer to the water recycling plant than the occupants of Rooms 4 and 5.
The plant has been targetted by some observers as a potential source of gas.
When Phuketwan last heard from American Ryan Kells, 31, who was travelling with Jill St Onge, he suggested via an email that he considered methane might be a cause.
But why were only the four people in those two rooms affected, not others? That remains part of the mystery.
Epidemiologists involved in the case told Phuketwan today from Bangkok that they had no knowledge of the latest check and were not involved.
Since the deaths, Ryan Kells has returned with his fiancee's ashes to the US while Ms Bergheim's younger, unidentified female travelling companion is believed to have returned to Norway.
This week the local newspaper in Los Altos, California, reported that Ryan Kells had returned to the town where he went to high school to be with his mother and father, Beby and John.
A report in the 'Los Altos Town Crier' said: ''Adding furor to the tragedy was the lack of responsiveness from authorities, according to Kells family members.''
John Kells was quoted as saying: ''Our objective is to make sure an investigation is thoroughly undertaken. Assumptions were made very quickly.''
At the time, the Kells flew flew to Bangkok to help their son cope with the ordeal.
'''We want to be very careful not to speculate,''' Mr Kells told the Crier. But both he and his son remain suspicious that the air conditioning carried a toxic gas.
Ryan Kells noticed a strong chemical odor when he and Miss St Onge checked in at the Laleena room on May 2.
Phi Phi, between the Krabi mainland and Phuket, is about 45 minutes by speedboat from Phuket and longer by ferry.
The Laleena opened a year before the 2004 tsunami swept over Phi Phi, killing more than 800 people.
Since then the island has fully recovered, with visitors continuing to holiday there in substantial numbers.
Phi Phi Mystery Deaths: The Room Maid's Account
Phi Phi Photo Album Thai guesthouse maids have a way of knowing what goes on and the maid at the Laleena on Phi Phi was close to two mysterious deaths. This is her account.
Phi Phi Mystery Deaths: The Room Maid's Account
Why Pursuing the Truth Matters for Tourism
Opinion/Analysis Does it matter if the truth is never known about mishaps that kill tourists on and around Phuket? It matters because of trust. Only once the whole truth is told can trust be restored.
Why Pursuing the Truth Matters for Tourism
Dead Tourist 'Pushed off Phi Phi': Boyfriend
Latest The boyfriend of an American who died in strange circumstances along with a Norwegian woman on Phi Phi has rejected suggestions that they argued.
Dead Tourist 'Pushed off Phi Phi': Boyfriend
Phi Phi Deaths: No Word on What Killed Women
Latest Inquiries were continuing today into the mysterious deaths of two women who occupied adjoining rooms at the same Phi Phi guesthouse. Several rumors have been discounted.
Phi Phi Deaths: No Word on What Killed Women
MediaWATCH: Tourist Death Theories Abound
Latest Internal Security Act coming for Phuket; International media seek clues to the deaths of two Phi Phi tourists; why travel is not dangerous; a swim to Burmese heroine Suu Kyi.
MediaWATCH: Tourist Death Theories Abound
Phi Phi Deaths: Paradise By Day, Party By Night
Take the Tour The deaths of two tourists on Phi Phi remain a mystery as speculation continues about the cause. The island, visited by day trippers in sunshine, also parties long and hard.
Phi Phi Deaths: Paradise By Day, Party By Night
Phi Phi Deaths: Cause 'May Take a Month or More'
Latest Relatives and friends of two women who died in strange circumstances on Phi Phi will probably have to wait several weeks before they learn the cause, and so will islanders.
Phi Phi Deaths: Cause 'May Take a Month or More'
Phuket Wan omits info Ryan Kells and female Karina Refsth, companions to the deceased were taken ill too, but recovered.
If those rooms were air conditioned and thus sealed off from fresh air, and a sewage smell was reported (in the Los Altos report; http://www.losaltosonline.com/index.php?option=com_content&task=view&id=17619&Itemid=46 )
then perhaps it was chemical fumes from the drains.
Editor: The article says: ''But why were only the four people in those two rooms affected, not others? That remains part of the mystery.''
Posted by Steven Green on May 24, 2009 09:35