Calcutta: A Calcutta High Court judge on Friday questioned the "reliability" of the Bengal government's dengue death report after a petitioner named four people who purportedly died of the disease but were not on the government's list furnished on Thursday.

"What is the reliability of the government's report, then?" Justice Arijit Banerjee asked advocate-general Kishore Dutta after going through the four death certificates, each of which read "dengue NS1 Antigen positive".

Justice Banerjee, sharing a bench headed by acting Chief Justice Jyotirmoy Bhattacharya, directed Dutta to check the certificates' authenticity with the government.

On Thursday, the state had told the court that 38 people had died of dengue in Bengal till November 15 this year, 23 of them in government hospitals and 15 in private hospitals. It said 22 other deaths in private hospitals were being probed to establish the cause.

On Friday, counsel for Jadavpur University researcher Deborshi Chakraborty, one of seven petitioners who have moved public interest pleas on the dengue outbreak, challenged the figures.

"Yesterday, the government had furnished a list of 23 people who had died at government hospitals. Today I am submitting the death certificates of four others who also died at government hospitals from dengue (before November 15)," advocate Srijib Chakrabarty said.

When Dutta later claimed the state had spent Rs 5 crore to spray larvicide, Justice Banerjee, who lives in Salt Lake, retorted: "But I did not find anyone spraying larvicide in my area."