Supporters of Bangladesh's ruling Awami League party led by Prime Minister Sheikh Hasina allegedly attacked an opposition leader's motorcade on Friday as it returned from a function in the nation's capital ahead of Dec. 30 elections, the latest show of the violence that frequently accompanies polling in the South Asian nation.

Jatiya Oikya Front spokesman Latiful Bari of told The Associated Press that the attack occurred while opposition leader Kamal Hossain visited a graveyard in Dhaka to commemorate the killings of intellectuals during the country's independence war against Pakistan in 1971.

The attackers vandalized several vehicles but Hossain was unhurt, Bari said.

Police official Mohammed Selimuzzaman said police were sent to the scene of the alleged attack and were investigating.

At least two people have died and dozens have been injured in different clashes across the country since election campaigning began Monday. Two supporters of the ruling party died when rival groups clashed after the campaigns kicked off.

Such violence is common around elections in Bangladesh, a parliamentary democracy. While clashes happen usually between rival political parties, infighting is also common after aspirants fail to win nominations. So far, however, there has been less campaign-related violence than in previous years.

The opposition said such attacks are designed to weaken them ahead of the poll, while the ruling party said the opposition was out to destabilize the election process, fearing defeat.

Hossain has emerged as a strong challenger to Hasina since the country's main opposition Bangladesh Nationalist Party led by former Prime Minister Khaleda Zia joined his opposition alliance front. Jamaat-e-Islami, the largest Islamist party in Bangladesh, has also joined the front. Most of its leaders have been hanged under Hasina for crimes stemming from the war for independence in 1971.

On Dec. 14, 1971 dozens of teachers, journalists and cultural personalities were kidnapped and killed by Bangladeshi collaborators of Pakistani soldiers. Bangladesh won the war two days later.

Hossain, a prominent lawyer and a former law minister, is not contesting the election, but his party activity has mobilized a considerable challenge to Hasina, who wants to return to office for a third consecutive time. Zia, who is serving jail terms for corruption, is Hasina's arch rival, and an appeals court recently ruled she was disqualified from running for Prime Minister.