Guwahati/Gangtok/Agartala, Sikkim reported its first coronavirus case and Arunachal Pradesh a fresh case while Assam registered 64 new cases in the past 24 hours, taking the state's total tally to 392 as on Sunday night.

Meanwhile, with the starting of domestic flight operations from May 25, different northeastern states have issued different Standard Operating Protocols (SOP) for the arriving passengers.

In Gangtok, Sikkim Health Secretary Pemba T. Bhutia said that the Himalayan state reported its first coronavirus case when a 25-year-old student who returned from Delhi last week tested positive on Saturday.

The student from Rabangla in South Sikkim district is admitted at Sir Thutob Namgyal Memorial Hospital in Gangtok. Hospital sources said his condition was stable.

A month after Arunachal Pradesh became coronavirus free, an Arunachal student who has returned back to the state from Delhi by bus along with 33 other people on May 18 has tested Covid-19 positive on Sunday.

The border state had become coronavirus free after its lone patient, a 31-year-old man who had attended the Tablighi Jamaat congregation in Delhi, was discharged from hospital on April 24.

In Manipur, three people, including a woman, tested positive on Saturday night taking the state's total cases to 32 with 28 of them active.

In Tripura, three people, who recently came from Delhi, tested positive on Sunday night taking the state's total Covid-19 positive cases to 194, which included 161 Border Security Force personnel and their kin. However, only 27 cases are active.

In Guwahati, Assam Health Minister Himanta Biswa Sarma said that 90 per cent of the 392 Covid-19 patients in the state have been reported from quarantine centres across the state. He said out of 33 districts, Dhemaji in eastern Assam has reported no coronavirus case, while Hojai in central Assam, had the highest number -- 77 -- of cases.

"So far by train and by road, 60,000 people, mostly from southern and western India, returned to Assam. Over 12 lakh people of the state are residing in different parts of the country," the minister told the media on Sunday evening.

He said that of the total positive cases, 39 cases were attendees of the Tablighi Jamaat's congregation in Delhi's Nizamuddin in March, 271 are due to inter-state travelling and remaining from unknown sources.

Out of the total cases, 57 people have been discharged from hospitals after they recovered from the disease and three migrated to other states, while four died, including a 16-year-old girl.

Sarma, who also holds the Finance portfolio, said that around 2,000 passengers would come to Assam daily by different domestic flights and all except those who would not remain in the city for more than 8 to 10 hours would have to be in a quarantine centre in hotels, guest houses and in educational institutions.

According to the SOP issued by Tripura, health authorities will collect samples of one among every five passengers.

The Meghalaya government in a notification said that after arrival by aircraft and railways up to Guwahati, the Transport Department would arrange buses to pick up the Meghalaya-bound people, who would be taken to Shillong or Tura for testing. These people would be kept in institutional quarantine for up to 48 hours till the test results of the samples are known.

A Mizoram government notification said that no person shall board any flight bound for Lengpui Airport in Aizawl without obtaining prior permission from Mizoram Home Department and any person arriving there without a movement permit shall not be allowed to leave the airport.