The Banu Thalaba incident at Dhu Qassah took place as a consequence of this tribe’s continued hostilities against the believers. The Prophet (p) sent out his companions to engage the enemy. While the Muslims came near the habitation of the enemy, they were ambushed. All the Muslims were killed, except for one.
This is not the first time Banu Thalabah had been hostile to Muslims. In Thi Amr (Dhu Amarr) and the expedition of Dhat Al-Riqa, they sided with other tribes and fought against the Muslims.
Kitab al-tabaqat al-kabir,By Ibn Sa’d – Ibn Sa’d:
“THE SARIYYAH OF MUHAMMAD IBN MASLAMMAH, TOWARDS DHU AL-QASSAH
Then occurred the sariyyah of Muhammad Ibn Maslamah against Dhu al-Qassah in the month of Rabi al-Akhir in the sixth year from the Hijrah of the Apostle of Allah. They (narrators) said: The Apostle of Allah despatched Muhammad Ibn Maslamah with ten men towards Banu Tha’labah and Banu Uwal, a branch of Banu Tha’labah who were at Dhu al-Qassah, lying at a distance of twenty-four miles from al-Madinah on the route of al-Rabadhah. They arrived there at night. The enemy had one hundred men. They surrounded them. They (parties) exchanged arrows for an hour in the night then al-A’rab (bediouns) attacked them with spears and killed them. Muhammad Ibn Maslamah fell wounded. His ankle was injured so he could not move. They stripped them off their clothes. Then a Muslim passed by Muhammad Ibn Maslamah. He bore him to al-Madinah. Then the Apostle of Allah, despatched Abu Ubaydah Ibn al-Jarrah with forty men to the site of people’s encounter. There they found no one…” 
“In this year the Messenger of God sent out Muhammad b. Maslamah with ten men in Rabi’i. The enemy lay wait for them until he and his companions went to sleep. Before they suspected anything, there was the enemy. The companions of Muhammad b. Maslamah were killed; Muhammad escaped wounded.” 
“THE EXPEDITION OF MUHAMMAD B. MASLAMA TO DHU L-QASSA
… The Prophet sent Muhammed b. Maslama with ten others, and they arrived upon them at night. The people hid until Ibn Maslama and his companions fell asleep. Then a hundred men surrounded them, and one did not know it except for the arrows that came to them. Ibn Maslama jumped up with his bow and shouted to his companions, ‘The weapons!’ They jumped up and aimed for an hour of the night. The Bedioun attacked with spears and killed three of them. The companions of Ibn Maslama joined him and killed one of them. The the people attacked and they killed the rest of Ibn Maslama’s companions. Muhammed b. Maslama fell wounded. His ankle was struck and he could not move. They stripped the dead of their garments and departed. A man passed by the dead and said, ‘To God may he return.’ When Ibn Maslama heard him, he knew he was a Muslim and he moved closer to him. The man gave Ibn Maslama food and drink and carried him until they arrived in Medina.” 
“A platoon led by Muhammad bin Maslamah set out towards the habitation of Bani Tha‘labah in Dhil Qassa. But a hundred men of the enemies ambushed and killed all of them except Muhammad bin Maslamah who managed to escape but badly wounded.” 
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 Kitab al-tabaqat al-kabir,By Ibn Sa’d, by Ibn Sa’d, volume 2, page 105
 The History of al-Tabari: The Victory of Islam: Muhammad at Madinah, [Michael Fishbein – Translator] volume 8, page 93
 The Life of Muhammad: Al-Waqidi’s Kitab Al-Maghazi [Translator: Rizwi Faizer], page 270
 Sealed Nectar (‘Ar-Raheeq Al-Makhtum’), By Safiur-Rahman Al-Mubarakpuri, page 147