China's judicial authorities said Sunday that the country will continue to maintain "high pressure" on corruption as authorities press on with a sweeping anti-graft drive.

A total of 22 Chinese ex-officials at ministerial level or above, including former leader Zhou Yongkang, were prosecuted last year while 41 were subject to formal investigations, up from 28 in 2014, Procurator-General Cao Jianming told lawmakers when presenting the Supreme People's Procuratorate's (SPP) work report for 2015.

Chief Justice Zhou Qiang also said Zhou and 15 other senior officials had been put on trial, showcasing "the Party and the country's resolute determination to crack down on corruption."

More than three years into the corruption campaign that targets both "tigers" and "flies," the terms assigned to different officials depending on their ranks and levels of corruption, there is little sign of losing momentum.

Just earlier this month, the Communist Party of China (CPC) Central Commission for Discipline Inspection announced an investigation into Wang Min, vice chairman of the Education, Science, Culture and Public Health Committee of the National People's Congress (NPC), for suspected violation of Party codes of conduct.

According to the SPP work report, almost 80 former Chinese officials at ministerial level or above had been investigated in the three years between 2013 and 2015.

"We will continue to maintain high pressure on corruption," Chief Justice Zhou said.

All in all, 54,249 officials were investigated for their involvement in 40,834 graft cases in 2015, according to Procurator-General Cao. The figures represent a slight drop from the year before, when 55,101 officials were probed in 41,487 cases.

They include 4,568 officials at division level and above and 769 officials at prefecture level and above.

On the "tigers" end, prosecutors looked into 4,490 graft, bribery and embezzlement cases that involved more than 1 million yuan (154,083 US dollars) each, Cao said.

More than 13,000 officials were investigated and punished for accepting bribes, in addition to over 8,200 for offering bribes.

On the "flies" end, more than 20,500 grassroots officials from the agricultural sector as well as land acquisition, social insurance, education and medicare services were investigated and punished, Cao said.

Both Cao and Zhou went on to pledge that more will be done to weed out graft in the judiciary. A total of 2,424 judicial staff were investigated and punished over graft in 2015, according to Cao Jianming, and Zhou Qiang vowed "zero tolerance" for judicial corruption.

"We will forge an effective anti-graft mechanism in which officials dare not, can not and will not be corrupted," Cao said. "Power shall be locked in the cage of regulations."

His words echoed a communique published in January after the conclusion of the sixth plenary session of the 18th CPC Central Commission for Discipline Inspection, which called for a heavy-handed approach against corruption "with unabated forces and unchanging rhythm."

Anti-graft officials will work to reduce corruption and prevent corruption cases from growing, according to the communique. Work also needs to be done to make sure officials "do not dare to be corrupt" and to strengthen the system so that officials "are unable and unwilling to be corrupt," it read.

Meanwhile, with the space for graft and power abuse considerably narrowed at home, China is also looking to further expand international cooperation in apprehending suspects who had fled overseas.

According to Procurator-General Cao, Chinese authorities brought back 124 corruption suspects from 34 countries and regions, who had previously on the run in a 17-month international manhunt.

Seventeen out of 100 wanted fugitives listed in an Interpol "red notice" were also netted, he said, adding that China will step up efforts with relevant countries and regions to bring those still at large to justice and explore ways to confiscate their illegal gains.

Chief Justice Zhou also pledged greater efforts from Chinese courts to improve court proceedings for fugitive graft suspects and to take a more proactive stance in the cross-border hunt-down.

Lawmakers, present Sunday for this year's annual session of the NPC, China's top legislature, hailed the achievements made past year in countering corruption but demanded more efforts to root out the pandemic.

Legislator and lawyer Liu Ling from east China's Jiangsu Province urged authorities to speed up the making of an anti-corruption law.

"We are in pressing need for a special legislation that could regulate anti-graft operations, protect whistleblowers, promote officials' assets declaration and coordinate work of disciplinary departments of the Party and the country's judicial organs," Liu said.

Hong Kong legislator Peter Wong Man Kong, meanwhile, called for "precision attacks" in the anti-corruption drive to help with deepening reforms across the board.

"The current anti-graft campaign came as the country sets out to deepen reforms and wage its final battle on poverty, thus, the counter-corruption drive should focus on these fields," he said, highlighting local government elections and grassroots agricultural services as top priorities.

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