The Shanghai government has denied allegations it attempted to cover up a suspected swine flu case on Tuesday. Local media reported yesterday that a Shanghai resident who recently returned from Mexico had sought medical attention from health authorities in Zhabei district. Tests ultimately proved that the man was not suffering from swine flu, the Shanghai Evening Post reported. Rumours of the case emerged on Tuesday, but calls by South China Morning Post reporters to Zhabei health authorities and the municipal government were met with a flat denial. Spokesmen said it was an 'ordinary fever' with no connection to the international flu outbreak. However, the Evening Post report yesterday said there had been considerable concern that the man - who had returned from Mexico via Brazil on Sunday - could have been carrying the disease that has sparked global fears of a pandemic. He had been kept in isolation throughout Tuesday and medical staff who treated him had gone into voluntary quarantine until the results of tests were known. The final all-clear was only given at midnight, the newspaper said. The patient checked out of hospital yesterday morning, just over 25 hours after he had been admitted. Responding to media questions at a regular press conference yesterday, Shanghai government spokesman Chen Qiwei denied there had been any attempt to conceal information from the press. 'This was not a suspected case. If it was a suspected case it would have followed a set procedure,' he said, but did not give details of the procedure or say what criteria were required before a patient would be considered a suspected case. Instead, he called on reporters to 'fully believe' the municipal government was committed to transparency in its efforts to contain the epidemic. '[On Tuesday] we did receive some phone calls from reporters, so we inquired to our top leaders immediately and confirmed from them that there was no such information. 'We issued our daily report saying that Shanghai has neither suspected nor confirmed cases. 'Today, we confirmed from relevant authorities again and the result is the same.'