QITAIHE, Heilongjiang - Rescuers were still struggling on Monday to reach 22 miners who have been trapped underground for a week in a flooded mine in northeast Heilongjiang province.

Rescuers reported that they heard "knocking sounds" at about 2 am Monday from within the Hengtai Coal Mine, located in the city of Qitaihe. They believe the knocking sounds may have been a response from the trapped miners, as the rescuers previously knocked on the sides of a 278-meter-deep hole that was drilled on Sunday night, hoping to establish communication with the miners.

Rescuers responded to the sounds by sending relief supplies down the hole at 9 am Monday, including food, a lamp, a pen and some paper. A rope tied to the package was shaken by an unknown force as it was lowered, leading rescuers to believe that the miners had been located.

However, when the rescuers pulled the package back out of the hole an hour and a half later, they found that it had not been opened.

Rescue teams are currently working to pump water out of the flooded mine in order to make it easier to reach the trapped miners. The flood occurred on August 23, when 45 miners were working underground - 19 managed to escape.

On Saturday, four of the 26 miners were confirmed to be alive. However, only three were brought above ground that day; the fourth was confirmed dead early Sunday morning. His body was retrieved at 3:30 am Sunday.

Li Guiying, 43, wife of miner Han Guowu, frowned with trepidation as she stood in the front of the family's waiting area.

"My husband is the breadwinner. He earns 6,000 yuan ($940) per month, which lets me to stay at home and take care of our two children, aged 4 and 12," Li said.

The reality that her husband has been trapped underground for about 150 hours sends chills down her spine. "What should I do if he dies?" Li murmured.

The mine is one of many that have been operating illegally in recent years, despite the government's efforts to shut down small, outdated mines. The provincial government previously ordered the mine to stop production in 2007. However, the owner restarted production without permission on August 16, according to the local work safety bureau.

The accident happened after the miners mistakenly drilled into a neighboring mine.

July's miraculous rescue, in which two miners who were trapped for 188 hours in a collapsed coal mine in south Guangxi Zhuang autonomous region were rescued, gives the anxious families hope.

Another triumph occurred in 2010 at the Wangjialing Coal Mine in north Shanxi province, where 115 workers were pulled out of the flooded coal mine 179 hours after the accident.