Pakistan media is reporting that the country's military is on high alert over a possible strike by India.
Monday's reports come after a ratcheting up of tension between the two countries following attacks in Mumbai last month which killed 163 people.
Kamal Hyder, Al Jazeera's correspondent in Pakistan, said the local media attributed its reports to military sources, who were confirming that the navy, air force and army were on red alert.
"The Pakistani air force have been seen visibly in a number of locations flying close to the Pakistani-India border in what is being described as an aggressive patrolling mode, following reports that India is planning pre-emptive strikes against locations in Pakistan," Hyder reported.
"Chiefs of the three forces are meeting in what is being described as an emergency meeting in general headquarters in Rawalpindi.
"Only after the meeting is over will we come to know if it is a red alert or a heightened state of alert."
Hyder said that observers are saying that the Congress party in India has lost prestige due to the Mumbai attacks and, therefore, may try a show of strength in Pakistan.
Delayed civilian flights
The Reuters news agency quoted a Pakistan airline official as saying the Pakistani air force had conducted an exercise on Monday causing delays to two civilian flights.
"Two of our flights were delayed for some time because the PAF was conducting some exercises, but now everything is back on normal," Muhammad Latif, a spokesman for Pakistan International Airlines, said.
The flights were delayed at the airport in Lahore, near the Indian border, Latif said, while dismissing television reports of a high alert at Pakistani airports.
An air force spokesman declined to comment when asked about an exercise, saying only: "In view of the current environment, the PAF has enhanced its vigilance."
Divya Gopalan, Al Jazeera's correspondent in Srinagar, in India-controlled Kashmir, said that the Indian media was looking at Monday's reports with some degree of scepticism.
"They are saying that Pakistan is creating an artificial war hysteria to divert attention from the fact that they are under pressure from the Indian security services to deal with the Mumbai terror attacks."
'No red alerts'
Asad Durrani, the former head of Pakistani intelligence, told Al Jazeera that Pakistan was asked to do more to deal with individuals behind the Mumbai attacks. He dismissed the notion that the two states were on the brink of war.http://english.aljazeera.net/news/asia/2008/12/20081222102547699277.html