The BJP alleged that the Congress MLAs "feared for their lives" under Chief Minister H.D. Kumaraswamy's coalition government.
Karnataka Congress legislators on Monday left a resort here where they have been residing since Friday and set out for their home constituencies, a party leader said.
"All the MLAs left the resort to return to their constituencies," Congress state unit chief Dinesh Gundu Rao told the media in Bengaluru.
Over 70 of the party's 80 legislators have been at the resort on the city's outskirts since late on Friday after a Congress Legislature Party (CLP) meeting was held by former Chief Minister Siddaramaiah at the state legislature building.
The CLP meet was held as a show of the party's strength amid alleged poaching attempts by the Bharatiya Janata Party (BJP).
"All our MLAs took a unanimous decision that we needed to be together to thwart the BJP's attempts to destabilize the Congress-JD-S coalition government," Rao said.
On Sunday, one of the legislators, Anand Singh, from Vijayanagara Assembly in Ballari district, was hospitalised after being injured in an alleged brawl with another party MLA at the resort.
The Congress leaders did not disclose the details of the attack or who was responsible for it.
The BJP alleged that the Congress MLAs "feared for their lives" under Chief Minister H.D. Kumaraswamy's coalition government.
"Congress MLAs fear for life under HDK government. Siddaramaiah preaches everyone of constitutional values. We demand Dinesh Gundu Rao and Siddaramaiah to immediately suspend their party MLA responsible for the attack on Anand Singh," the BJP tweeted.
A major political drama was unfolded in the southern state last week when lawmakers from both BJP and Congress went missing.
In the 224-member Assembly, BJP has 104 members, Congress-79, JDS 37, BSP, KPJP and Independent one each, besides Speaker. BSP, KPJP and an Independent are supporting the coalition.
