Prime Minister Yingluck Shinawatra on Friday denied as groundless a report that her fugitve brother Thaksin recently visited Chiang Rai in his personal jet, landing at Mae Fah Luang airport.
A government spokesman had earlier confirmed that the report was a baseless rumour, she said.
Ms Yingluck said she had no idea why the rumour was spread and asked the media to be careful and report only confirmed information, otherwise it would just spread confusion.
Asked about the Office of the Ombudsman’s request that she explain why a valid Thai passport was reissued to the fugitive former prime minister, Ms Yingluck said the Foreign Ministry would have to make the needed clarification.
The prime minister said the decision over whether or not to return Mr Thaksin's passport to him was a matter for the Foreign Ministry and she had never interfered in the matter.
Ms Yingluck said that an allegation by the Democrat Party that the government had threatened to remove chiefs of district police stations in Bangkok if their subordinates did not support Pheu Thai candidate for Bangkok governor Pol Gen Pongsapat Pongcharoen, was also baseless.
Police were duty bound to ensure people's safety and the gubernatorial election would be free and fair and without any disruption, she said.
Questioned whether the Pheu Thai Party was confident Pol Gen Pongsapat would win the election, Ms Yingluck said she could not say at this time and would have to wait for election day.
She believed voters would choose the best candidate, based on his or her policies, to run the Bangkok Metropolitan Administration.
Ms Yingluck said she hoped the election campaign would be constructive and comply with regulations.
She did not want the campaign to become dominated by allegations and counter allegations, but be a forum for proposed policies that voters could consider in making their decision.
Most poll results show that about 40% of eligible voters have yet to make a decision how they would vote and were waiting to see all the candidates' policies, she added.