Zhuang Liehong, a former Wukan protest leader who fled to the United States in 2014, said his father was among those who were "violently arrested" by police in the raids, which took place at 3am local time.
"The raids led to confrontations which lasted until noon," said Zhuang, who keeps in regular contact with villagers.
He said that villagers told him more than 100 people were detained in the clashes.
Images being shared on Chinese social media show scores of residents embroiled with clashes with riot police. Many were wearing motorcycle helmets, some were waving Chinese national flags, while others were hurling stones.
The images also showed villagers with serious injuries. Some were covered with blood, while others had dark red markings on their bodies showing where they had been hit with plastic bullets.
"The police were detaining residents up until about 3pm," said one local villager, who did not want to be named. "They were old people, women and young kids, and many were left injured," the villager told the Telegraph.
"The police were firing at villagers like they were birds," another source said. "Some are old people and women. I am not sure if anyone died from the rubber bullets, but I am sure that they were seriously wounded."
Zhuang also sent the Telegraph several videos which appeared to show a tense standoff between security and residents inside the village, which had been placed under a lockdown.
Sources also said that authorities had been appealing for information on five men who they claim were involved in the protests, and a bounty of 100,000 yuan had been placed on their heads.
The local Public Security Bureau said took action in Wukan to restore stability to the village.
An official had told state media earlier this week that the local government had "addressed all of the Wukan villagers' legitimate demands for land".
Beijing fears any signs of discontent against its rule. It is deeply suspicious of moves towards greater freedoms in Hong Kong, which is only a four hour drive from Wukan, and is concerned that such demands could spill over into the mainland.