Hezbollah as well as groups and individuals affiliated to it have won at least 67 seats in Lebanon’s 128-member parliament, according to the results cited by politicians and campaigns and reported in Lebanese media on Monday.
Hezbollah's allies include the Amal Movement led by Parliament Speaker Nabih Berri and the Christian Free Patriotic Movement founded by President Michel Aoun.
Lebanon's first parliamentary elections in nine years was held on Sunday, with over 500 candidates vying for seats. Turnout was 49.2 percent, according to officials.
Videos posted on social media showed people in southern Lebanon celebrating the victory of Hezbollah and its allies.
Israel reacted to the results with typical animosity, with the regime's education minister Naftali Bennett saying Hezbollah's gains showed that the state is indistinguishable from the group and that Tel Aviv should not distinguish between them in any future war.
"Hezbollah = Lebanon," Bennett said on Twitter on Monday. Israel "will not differentiate between the sovereign State of Lebanon and Hezbollah, and will view Lebanon as responsible for any action from within its territory," he wrote.
Lebanon's parliamentary elections have been delayed three times since 2009 due to the crisis in neighboring Syria as well as disagreements over the new electoral law.
The parliamentary seats are split evenly - 64 for Christians and 64 for Muslims including Druze, with the two halves further divided among 11 religious groups.
The elections were held under a new electoral law passed in June 2017 after years of wrangling.
The new system reduced the number of voting districts from 26 to 15. It also replaced the current plurality system with a system of proportional representation, increasing the sectarian diversity of lawmakers within each district.
The unofficial results also showed that Prime Minister Saad al-Hariri would emerge as the Sunni leader with the biggest bloc in the parliament, making him the frontrunner to form the next government even though he lost seats.
Under a power-sharing agreement that ended the 1975-1990 civil war in Lebanon, prime minister must be a Sunni Muslim, president a Maronite Christian and parliament speaker a Shia Muslim.
An anti-Hezbollah alliance led by Hariri and supported by Saudi Arabia won a majority in the Lebanese parliament in 2009, but it has since disintegrated.