Holding a second Jama`ah (congregational) prayer in a mosque which has a regular Imam is subject to debate among the Muslim scholars, though the opinion which says that there is nothing wrong in holding a second Jama`ah in the mosque carries more weight, particularly if there are valid reasons for holding a second Jama`ah in the same mosque.
Following is the fatwa issued by Al-Azhar House of Fatwa in this regard: “This issue is controversial among jurists. The Hanafi, Maliki, and Shafi`i scholars maintain that it is Makruh(disliked) to hold a second Jama`ah in the Masjid (mosque) that has a regular Imam. The reason behind this is that it might cause dissension and hatred among people, besides some evil people may take advantage of this to delay the first Jama`ah so that they could pray with an Imam who agrees with their own sect or innovated way of religion. To prevent such dissension and evil schemes, the afore-mentioned jurists hold that it is not permitted to hold a second Jama`ah in the same Masjid where there is a regular Imam.
However, Imam Ahmad, Is-haq, Ibn Al-Mundhir and – according to At-Tirmidhi – some Companions of the Prophet and their successors maintain that there is nothing wrong in people holding a second Jama`ah if the regular scheduled Jama`ah has already been over for the same prayer. They base their argument on the hadith reported by Imam Ahmad in his Musnad and Abu Dawud in his Sunan and At-Tirmidhi on the authority of Abu Sa`id Al-Khudri (may Allah be pleased with him) who entered a Masjid after the Prophet (peace and blessings be upon him) had prayed, then the Prophet (peace and blessings be upon him) said: “Who would like to give this man a charity by praying with him?” Then a man (Abu Bakr, may Allah be pleased with him) came up and prayed with him.
Reviewing these views, we conclude that the second opinion is the most correct.
As for the Masjid which does not have a regular Imam, it is held by consensus that it is not disliked to have a second Jama`ah.”

Dr. Salah Sultan, President of the Islamic American University and professor of Islamic Jurisprudence, Cairo University, adds: “The pressing needs of the Muslim communities in the West to hold more than one Jama`ah – or even Jumu`ah (Friday Prayer) – in the same mosque owing to valid reasons such as the limited space of the mosques give preference to the view that allows doing so.
For instance, Adam Mosque in Washington D.C. offers Jumu`ah five times on Friday and Dar Al-Hijrah mosque in Virginia does it three times.”