When Israeli police detained Muna al-Kurd and issued a summons for her twin brother, Muhammad, their millions of followers on social media raised an alarm.

The 23-year-olds are at the center of efforts to stop Israeli settlers from evicting tens of Palestinian families from their homes in East Jerusalem’s Sheikh Jarrah neighborhood — clashes over which played a role in sparking the 11-day conflict between Israel and Hamas last month.

After less than a day in custody, the two were released Sunday without any charges filed, said their father, Nabil al-Kurd. A police spokesperson said the two were detained on “suspicion of participating in riots” in Sheikh Jarrah. The sister and brother said the arrests were efforts to silence their activism.

They were far from alone. In recent weeks, a campaign of detentions has swept up Palestinians in East Jerusalem and Arab citizens all over Israel, amid an ongoing surge in Palestinian activism and on the heels of the worst communal violence in years.

Israeli police have arrested more than 2,100 people and issued 380 indictments against 184 people as part of a campaign that began in May. More than 91 percent of those arrested have been Arab, the Haaretz newspaper reported, citing police sources. Israel’s Arab citizens, many of whom identify as Palestinian, make up about 20 percent of the country’s 9 million citizens. Most of the 350,000 Palestinian residents of East Jerusalem are not Israeli citizens.

The campaign has added to the grievances of many Arab Israelis, who accuse police of escalating violence against them and resorting to undue force and frequent arrests — while deprioritizing violence by Jewish Israelis.

Detainees and lawyers have also alleged incidents of police brutality and violence inside police stations.

“This wave is unprecedented,” said Wesam Sharaf, a lawyer for Adalah, the Legal Center for Arab Minority Rights in Israel, based in Haifa. He said Israel was using “arrests as a punishment for the whole society and as a means of deterrence” against Palestinian activism.

“The very low percentage of indictments indicates that this is not for the purpose of applying the law,” he said. “We have seen police implement the law differently for two different groups … which makes it seem that this specific wave of arrests has been specifically aimed against Palestinian Arabs.”

A spokesperson for the Israeli police rejected the accusation in a WhatsApp message, writing that the police have “acted in an equal and impartial manner.”

“In any situation of public disturbance, the police endeavored to conduct a dialogue with rioters without [resorting to] arrest or use of a variety of means,” the statement said.

The wave of arrests began the second week of May amid the 11-day conflict between Israel and Hamas, which in part sparked the largest protests in decades by Israel’s Arab citizens and the worst communal violence between Jews and Arabs in years. The escalations followed weeks of unrest around Sheikh Jarrah and the al-Aqsa Mosque in Jerusalem, during which many Palestinians were arrested and injured amid near-daily confrontations with police.

The worst of the communal violence — in which synagogues, mosques and shops were looted and drivers were attacked by mobs for being either Jewish or Arab — has since subsided. But many Arab Israelis say they still do not feel safe after what they have described as an unequal response by police to attacks by far-right Jewish Israelis. For years, violent crime and gun violence have plagued many impoverished Arab communities in Israel. Despite calls to address the issue, Arab leaders say, police and politicians are slow to respond or absent unless Jewish victims are involved.

The Israeli police in an online statement said that their “Law and Order” campaign, which formally ended Thursday, targeted “rioters and criminals.” They also said they confiscated 970 illegal weapons and issued 1,500 reports for road and vehicle violations as part of their operations.

“The Israeli Police will continue to enforce the law equally, with discretion, and all with the aim of maintaining public peace, property and safety,” the police spokesperson told The Washington Post.

Sharaf, the Adalah lawyer, said the majority of those detained were male high school and university students. He estimated that 20 percent were minors. Some were arrested in or around protests, while others were detained in raids on their homes. Although the vast majority were not charged, a police arrest record could affect future opportunities, Sharaf said. Some were released on condition of paying a fine or remaining away from their hometowns or parts of Jerusalem for short periods.

Many of those charged with crimes were accused of attacking a police officer or disturbing the work of a police officer, Sharaf said. He said these charges are often used when people are arrested at lawful protests. Other cases included charges of incitement, which in Israel is a serious offense.

For Omaiyer Lawabne, a 20-year-old resident of Nazareth, in northern Israel, life has remained on hold since he said he was arrested and beaten by police in Nazareth, an Arab-majority city, on the evening of May 12.

Lawabne said he had not joined demonstrations that night, at the end of the holy month of Ramadan, because he had heard there would be a heavy police presence. When he went out to get cash from an ATM, he said, he chose one far from the protests.

But as he exited his car, riot police charged at him and threw sound grenades, he said. Frightened, he ran. Eventually, he said, police caught up and beat him, even though he was not resisting arrest.

He was taken to the Nazareth police station and beaten again along with other detainees, he said. He started bleeding from his head and requested medical attention several times. He was then transferred to a hospital, where he received four stitches, he said.

Lawabne said the police did not charge him with any crime. His brother, who was with him that night, was arrested and charged with a security-related crime, a very serious offense, he said.

Lawabne’s case has been taken up by Adalah, which on Monday took legal action with a formal complaint to Israeli officials “regarding serious failures on the part of Israeli police and investigators in Nazareth that amount to grave criminal offenses,” according to the organization’s brief.

A spokesperson for the Israeli police said officers “dealt with a large number of violent incidents” over a brief window in time, including stones and fireworks being thrown at police and civilians. The spokesperson said that defense lawyers and medical workers were at the Nazareth station and that “any detainee in need of medical treatment was transferred without delay and, in some cases, was summoned for questioning only after treatment.”

Lawabne said he is now easily fatigued but has trouble sleeping. When he does sleep, he dreams of the police.

“That they are chasing me,” he said. “That they want to throw me into the ocean and I need to swim the entire ocean to live.”