The ISPR said that the terrorists attempted to force their way into the hotel and were challenged by the security guard, who was sacked at and lost his life.
The report further said that additional police force, ATF (anti-terrorism force) and army have been called in to handle the situation. Balochistan Home Minister Ziaullah Langove said most guests had been evacuated from the five-star Pearl Continental Hotel, which helicopters circled as fighting was underway.
The city of Gwadar, including its major hotels, is heavily guarded by the Pakistan army and paramilitary forces.
All the guests were safely evacuated from the hotel.
Mohammad Aslam, the on-duty officer in Gwadar, said he could hear gunfire but that the operation was coming to an end.
The Pearl Continental in Gwadar is a popular accommodation and meeting place for business travelers, many of them connected to the ambitious development and transportation project there that is a centerpiece of Beijing's burgeoning economic and political alliance with Pakistan.
Inspector General of Police (IGP) Mohsin Hassan Butt also confirmed that "two to three gunmen had first fired at and then entered the hotel".
Last month, 14 Pakistani security personnel were forced out of passenger buses near Gwadar in the main coastal highway and shot dead in an attack claimed by a separatist Baloch militant group.
But Balochistan, the largest and poorest province, remains an exception and there have been several attacks this year.
China is investing heavily in Balochistan under the Dollars 50 billion China Pakistan Economic Corridor (CPEC).
The CPEC, launched in 2015, is a planned network of roads, railways and energy projects linking China's resource-rich Xinjiang Uyghur Autonomous Region with Pakistan's strategic Gwadar Port on the Arabian Sea.