Ukrainian President Petro Poroshenko has formally refused to accept the resignation of the country’s prosecutor-general, who has been criticized for the handling of a probe into the death of an anticorruption activist in an acid attack.

Calls for Yuriy Lutsenko to step down intensified after Kateryna Handzyuk died on November 4, three months after she was injured in an acid attack.

Lutsenko on November 7 formally submitted his resignation to Poroshenko, a day after parliament -- namely, the president’s bloc -- refused to back the move.

In a statement on November 9, Ukraine’s presidential press service cited the parliament’s “vote of confidence” in Lutsenko as the reason why Poroshenko had refused to accept his resignation, adding “important tasks are ahead” of Lutsenko, a presidential appointee.

The announcement by Poroshenko’s office comes just hours after a top EU official said in Kyiv that the international community was “deeply shocked” by the death of Handzyuk.

“It’s something we cannot accept,” EU Enlargement Commissioner Johannes Hahn told a press conference in the Ukrainian capital on November 9.

He urged the Ukrainian government to identify and punish those behind the attack, saying “The international community pays attention.”

Hahn also delivered a fresh EU report on Ukraine to Prime Minister Volodymyr Hroysman.

In that document, the EU emphasized that Ukraine's authorities must properly investigate attacks against civil society activists and punish the perpetrators.

Five suspects, including a police officer, have been arrested on suspicion of involvement in the attack on Handzyuk, but authorities have not described a specific potential motive for the attack.

Several dozen local NGOs signed a letter earlier this week criticizing the "apparent failure" of Ukraine's law enforcement system to investigate attacks on civil society activists.

They also called on Interior Minister Arsen Avakov, as well as Lutsenko, to resign amid charges they have blocked the investigation.

With reporting by AFP and Pravda.ua