KABUL — The former director's desk was empty of clutter, the bowl of nuts and raisins for visitors untouched. Down the hall, the dazed staff went through the motions of finishing year-end reports. The newly named director sagged sadly in an armchair, reluctant to sit in his old friend's place. Finally he straightened, struggling for composure.

“This was not a simple crime,” Naim Asghari said. “They were waiting at the speed bump down the block from his house. They shot his driver, then they opened the other door and shot Mr. Rasheed, 10 or 12 times. Then they were gone. Nobody knows who planned this terror, nobody knows why.”

He shook his head. “I am still in shock,” he said. “We all are. We never thought this could happen. Why would anyone want to kill him?”

The unclaimed Dec. 23 assassination of Yousuf Rasheed, 45, the executive director of the nonprofit Free and Fair Election Forum of Afghanistan, was among at least two dozen targeted killings of Afghan journalists, civic activists, religious scholars and government employees in recent months.

 On Saturday, Afghan authorities announced that they had caught two Taliban members who confessed to killing Rasheed with four accomplices, after disguising themselves as students. They said the group belonged to a Taliban cell that has been orchestrating targeted attacks.

“The Taliban’s conscience, if they have one, must tremble and rot from the bloodshed of activists,” said First Vice President Amrullah Saleh, a former national intelligence chief, who made the announcement.

But the insurgents, who resumed peace talks with Afghan leaders in Qatar last week, have repeatedly denied any connection with the recent individual slayings. Some victims were ambushed and shot, others blown up by bombs affixed to their vehicles.

Until now, no other cases have been reported solved and no official tally of the toll has been released. Meanwhile, the specter of a silent, invisible threat has created wider fears and raised speculation about an array of possible origins and motives, from rogue security units to rival Islamic extremists to copycat killers with personal or political vendettas.

Rasheed’s murder has seemed incomprehensible to those who knew him as a quiet, methodical professional, or looked up to him as a role model. It has reverberated far beyond the obscure office where he organized youthful poll-watchers on national election days, pored over sheaves of precinct results, and prepared reports of both fraud complaints and Taliban threats.

Across the informal but closely connected network of public interest and pro-democracy advocates in the Afghan capital, his killing has cast a pall of paralyzing doubt and fear. Most members are young, educated men and women who grew up during the country’s fledgling experiment in post-Taliban democracy, then took various paths to promote and defend it.

“Yousuf Rasheed was my friend and my hero. Since he was killed, all our activity has stopped,” said Khalil Raufi, 30, who heads a consortium of groups called the Civil Society and Human Rights Activists Network. He said many of its members are now turning down TV interviews, working mostly from home and meeting only via Zoom.

Raufi and several associates, who agreed to meet with a Washington Post reporter inside a fortified hotel, said they had no protection of any kind and no means to afford the tinted-glass SUVs and armed guards that powerful politicians and business owners use. They complained that police and government officials had done little to reassure the community or provide concrete protection after the targeted killings started.

“The fear stays in my head all the time now,” said Mobeen Aimaq, 26, who was shot and wounded two years ago by an unknown assailant while researching parliamentary elections. “Whenever I am outside, I look around and behind me constantly.”

Since the rash of targeted killings started, the Afghan government has come under intense public pressure to respond. It has doubled the number of police patrolling Kabul streets and this week announced it will install security cameras throughout the capital. But until Saturday, none of the individual cases had been announced as solved.

On Wednesday, the insurgent group’s spokesman in Qatar said in a WhatsApp media message that unknown attackers are seeking to sow confusion at a crucial juncture, “besmirch” the Taliban and undermine the “establishment of peace and an Islamic system” in the country.

Some activists and journalists have reportedly fled the country. Raufi said he had been invited to a conference in Canada last month and that his worried family begged him not to come back.

“They told me to save myself,” he said. “I want to be here. We are trying to save everything our society gained over the past 20 years. But we all need more protection.”

Although the Taliban — which opposes modern democracy and seeks to impose strict Islamist law — may be the likeliest source of the recent killings, Raufi and other activists said they have also been denounced by conservative Afghans who see them as promoting liberal Western ideas, and have made political enemies by criticizing election fraud and official corruption.

Many have trained with international organizations, such as the Asia Foundation, various European foundations, and the U.S.-based National Democratic Institute, where Rasheed worked for five years. But they see their role as watchdogs rather than rabble-rousers, and despite the Taliban’s antagonism to their values, few had faced serious personal threats until recently. Now, danger seems to lurk everywhere.

Rasheed’s former colleagues are especially bewildered. In a lengthy conversation in the Election Forum office last week, Asghari and two other staffers said he had no enemies and no partisan ties, had insisted on impartiality in assessing elections, and had even tried to play a neutral role in making recommendations to improve the Taliban peace talks.

“He pushed for a sustainable peace, not a hurried one that would bring political benefits to anyone. He was always talking about improving the political process. He was fair,” Asghari said.

Rasheed lived a relatively simple life, his colleagues recalled. He raised five children with his wife in a quiet Kabul suburb, shopping on weekends and often counseling friends who had family or business problems. He traveled abroad for meetings but felt more comfortable at home, even as war and violence continued to afflict Afghan society, they said.

But colleagues said Rasheed’s life became far more public, and more complicated, when he was named to head the election forum after the 2014 presidential election. He had to start competing for institutional funding with other groups, and he often appeared on TV newscasts and panels as an election expert. His rising profile alone may have made him a target.

“He didn’t change as a person. He still believed in treating others as equals, but he became a leader,” Raufi said.

For now, public interest activists in Kabul are trying to keep as low a profile as possible. After meeting in the hotel last week, Raufi and his two friends donned black face masks as they exited to the street. It was not, they said, for fear of the coronavirus.